WorldWideScience

Sample records for chromosome axis remodeling

  1. Meiotic double-strand breaks at the interface of chromosome movement, chromosome remodeling, and reductional division

    OpenAIRE

    Storlazzi, Aurora; Tessé, Sophie; Gargano, Silvana; James, Françoise; Kleckner, Nancy; Zickler, Denise

    2003-01-01

    Chromosomal processes related to formation and function of meiotic chiasmata have been analyzed in Sordaria macrospora. Double-strand breaks (DSBs), programmed or γ-rays-induced, are found to promote four major events beyond recombination and accompanying synaptonemal complex formation: (1) juxtaposition of homologs from long-distance interactions to close presynaptic coalignment at midleptotene; (2) structural destabilization of chromosomes at leptotene/zygotene, including sister axis separa...

  2. SWI1 Is Required for Meiotic Chromosome Remodeling Events

    Institute of Scientific and Technical Information of China (English)

    Kingsley A.Boateng; Xiaohui Yang; Fuqui Dong; Heather A.Owen; Christopher A.Makaroff

    2008-01-01

    The Arabidopsis dsy10 mutant was previously identified as being defective in the synapsis of meiotic chromosomes resulting in male and female sterility.We report:here the molecular analysis of the mutation and show that it represents a T-DNA insertion in the third exon of the SWI1 gene.Four mutations have now been identified in SWI1, several of which exhibit different phenotypes.For example.the swi1-1 and dyad mutations only affect meiosis in megasporocytes,while the swi1-2 and dsy10 mutations block both male and female meiosis.Furthermore,as part of a detailed cytological characterization of dsy10 meiocytes,we identified several differences during male meiosis between the swi1-2 and dys10 mutants, including variations in the formation of axial elements,the distribution of cohesin proteins and the timing of the premature loss of sister chromatid cohesion.We demonstrate that dsy10 represents a complete loss-of-function mutation,while a truncated form of SWI1 iS expressed during meiosis in swi1-2 plants.We further show that dys10 meiocytes exhibit alterations in modified histone patterns.including acetylated histone H3 and dimethylated histone H3-Lysine 4.

  3. Condensin-driven remodelling of X chromosome topology during dosage compensation

    Science.gov (United States)

    Crane, Emily; Bian, Qian; McCord, Rachel Patton; Lajoie, Bryan R.; Wheeler, Bayly S.; Ralston, Edward J.; Uzawa, Satoru; Dekker, Job; Meyer, Barbara J.

    2015-07-01

    The three-dimensional organization of a genome plays a critical role in regulating gene expression, yet little is known about the machinery and mechanisms that determine higher-order chromosome structure. Here we perform genome-wide chromosome conformation capture analysis, fluorescent in situ hybridization (FISH), and RNA-seq to obtain comprehensive three-dimensional (3D) maps of the Caenorhabditis elegans genome and to dissect X chromosome dosage compensation, which balances gene expression between XX hermaphrodites and XO males. The dosage compensation complex (DCC), a condensin complex, binds to both hermaphrodite X chromosomes via sequence-specific recruitment elements on X (rex sites) to reduce chromosome-wide gene expression by half. Most DCC condensin subunits also act in other condensin complexes to control the compaction and resolution of all mitotic and meiotic chromosomes. By comparing chromosome structure in wild-type and DCC-defective embryos, we show that the DCC remodels hermaphrodite X chromosomes into a sex-specific spatial conformation distinct from autosomes. Dosage-compensated X chromosomes consist of self-interacting domains (~1 Mb) resembling mammalian topologically associating domains (TADs). TADs on X chromosomes have stronger boundaries and more regular spacing than on autosomes. Many TAD boundaries on X chromosomes coincide with the highest-affinity rex sites and become diminished or lost in DCC-defective mutants, thereby converting the topology of X to a conformation resembling autosomes. rex sites engage in DCC-dependent long-range interactions, with the most frequent interactions occurring between rex sites at DCC-dependent TAD boundaries. These results imply that the DCC reshapes the topology of X chromosomes by forming new TAD boundaries and reinforcing weak boundaries through interactions between its highest-affinity binding sites. As this model predicts, deletion of an endogenous rex site at a DCC-dependent TAD boundary using

  4. Phosphorylation of chromosome core components may serve as axis marks for the status of chromosomal events during mammalian meiosis.

    Directory of Open Access Journals (Sweden)

    Tomoyuki Fukuda

    2012-02-01

    Full Text Available Meiotic recombination and chromosome synapsis between homologous chromosomes are essential for proper chromosome segregation at the first meiotic division. While recombination and synapsis, as well as checkpoints that monitor these two events, take place in the context of a prophase I-specific axial chromosome structure, it remains unclear how chromosome axis components contribute to these processes. We show here that many protein components of the meiotic chromosome axis, including SYCP2, SYCP3, HORMAD1, HORMAD2, SMC3, STAG3, and REC8, become post-translationally modified by phosphorylation during the prophase I stage. We found that HORMAD1 and SMC3 are phosphorylated at a consensus site for the ATM/ATR checkpoint kinase and that the phosphorylated forms of HORMAD1 and SMC3 localize preferentially to unsynapsed chromosomal regions where synapsis has not yet occurred, but not to synapsed or desynapsed regions. We investigated the genetic requirements for the phosphorylation events and revealed that the phosphorylation levels of HORMAD1, HORMAD2, and SMC3 are dramatically reduced in the absence of initiation of meiotic recombination, whereas BRCA1 and SYCP3 are required for normal levels of phosphorylation of HORMAD1 and HORMAD2, but not of SMC3. Interestingly, reduced HORMAD1 and HORMAD2 phosphorylation is associated with impaired targeting of the MSUC (meiotic silencing of unsynapsed chromatin machinery to unsynapsed chromosomes, suggesting that these post-translational events contribute to the regulation of the synapsis surveillance system. We propose that modifications of chromosome axis components serve as signals that facilitate chromosomal events including recombination, checkpoint control, transcription, and synapsis regulation.

  5. ATM promotes the obligate XY crossover and both crossover control and chromosome axis integrity on autosomes.

    Directory of Open Access Journals (Sweden)

    Marco Barchi

    2008-05-01

    Full Text Available During meiosis in most sexually reproducing organisms, recombination forms crossovers between homologous maternal and paternal chromosomes and thereby promotes proper chromosome segregation at the first meiotic division. The number and distribution of crossovers are tightly controlled, but the factors that contribute to this control are poorly understood in most organisms, including mammals. Here we provide evidence that the ATM kinase or protein is essential for proper crossover formation in mouse spermatocytes. ATM deficiency causes multiple phenotypes in humans and mice, including gonadal atrophy. Mouse Atm-/- spermatocytes undergo apoptosis at mid-prophase of meiosis I, but Atm(-/- meiotic phenotypes are partially rescued by Spo11 heterozygosity, such that ATM-deficient spermatocytes progress to meiotic metaphase I. Strikingly, Spo11+/-Atm-/- spermatocytes are defective in forming the obligate crossover on the sex chromosomes, even though the XY pair is usually incorporated in a sex body and is transcriptionally inactivated as in normal spermatocytes. The XY crossover defect correlates with the appearance of lagging chromosomes at metaphase I, which may trigger the extensive metaphase apoptosis that is observed in these cells. In addition, control of the number and distribution of crossovers on autosomes appears to be defective in the absence of ATM because there is an increase in the total number of MLH1 foci, which mark the sites of eventual crossover formation, and because interference between MLH1 foci is perturbed. The axes of autosomes exhibit structural defects that correlate with the positions of ongoing recombination. Together, these findings indicate that ATM plays a role in both crossover control and chromosome axis integrity and further suggests that ATM is important for coordinating these features of meiotic chromosome dynamics.

  6. TWEAK-Fn14 cytokine-receptor axis: a new player of myocardial remodeling and cardiac failure

    Directory of Open Access Journals (Sweden)

    Tatyana eNovoyatleva

    2014-02-01

    Full Text Available Tumor necrosis factor (TNF has been firmly established as a pathogenic factor in heart failure, a significant socio-economic burden. In this review we will explore the role of other members of the TNF/TNF receptor superfamily (TNFSF/TNFRSF in cardiovascular diseases (CVDs focusing on TWEAK and its receptor Fn14, new players in myocardial remodeling and heart failure. The TWEAK/Fn14 pathway controls a variety of cellular activities such as proliferation, differentiation and apoptosis and has diverse biological functions in pathological mechanisms like inflammation and fibrosis that are associated with CVDs. Furthermore, it has recently been shown that the TWEAK/Fn14 axis is a positive regulator of cardiac hypertrophy and that deletion of Fn14 receptor protects from right heart fibrosis and dysfunction. We discuss the potential use of the TWEAK/Fn14 axis as biomarker for CVDs as well as therapeutic target for future treatment of human heart failure based on supporting data from animal models and in vitro studies. Collectively, existing data strongly suggest the TWEAK/Fn14 axis as a potential new therapeutic target for achieving cardiac protection in patients with CVDs.

  7. Fluoxetine induces input-specific hippocampal dendritic spine remodeling along the septotemporal axis in adulthood and middle age.

    Science.gov (United States)

    McAvoy, Kathleen; Russo, Craig; Kim, Shannen; Rankin, Genelle; Sahay, Amar

    2015-11-01

    Fluoxetine, a selective serotonin-reuptake inhibitor (SSRI), is known to induce structural rearrangements and changes in synaptic transmission in hippocampal circuitry. In the adult hippocampus, structural changes include neurogenesis, dendritic, and axonal plasticity of pyramidal and dentate granule neurons, and dedifferentiation of dentate granule neurons. However, much less is known about how chronic fluoxetine affects these processes along the septotemporal axis and during the aging process. Importantly, studies documenting the effects of fluoxetine on density and distribution of spines along different dendritic segments of dentate granule neurons and CA1 pyramidal neurons along the septotemporal axis of hippocampus in adulthood and during aging are conspicuously absent. Here, we use a transgenic mouse line in which mature dentate granule neurons and CA1 pyramidal neurons are genetically labeled with green fluorescent protein (GFP) to investigate the effects of chronic fluoxetine treatment (18 mg/kg/day) on input-specific spine remodeling and mossy fiber structural plasticity in the dorsal and ventral hippocampus in adulthood and middle age. In addition, we examine levels of adult hippocampal neurogenesis, maturation state of dentate granule neurons, neuronal activity, and glutamic acid decarboxylase-67 expression in response to chronic fluoxetine in adulthood and middle age. Our studies reveal that while chronic fluoxetine fails to augment adult hippocampal neurogenesis in middle age, the middle-aged hippocampus retains high sensitivity to changes in the dentate gyrus (DG) such as dematuration, hypoactivation, and increased glutamic acid decarboxylase 67 (GAD67) expression. Interestingly, the middle-aged hippocampus shows greater sensitivity to fluoxetine-induced input-specific synaptic remodeling than the hippocampus in adulthood with the stratum-oriens of CA1 exhibiting heightened structural plasticity. The input-specific changes and circuit

  8. Cytotoxic chromosomal targeting by CRISPR/Cas systems can reshape bacterial genomes and expel or remodel pathogenicity islands.

    Directory of Open Access Journals (Sweden)

    Reuben B Vercoe

    2013-04-01

    Full Text Available In prokaryotes, clustered regularly interspaced short palindromic repeats (CRISPRs and their associated (Cas proteins constitute a defence system against bacteriophages and plasmids. CRISPR/Cas systems acquire short spacer sequences from foreign genetic elements and incorporate these into their CRISPR arrays, generating a memory of past invaders. Defence is provided by short non-coding RNAs that guide Cas proteins to cleave complementary nucleic acids. While most spacers are acquired from phages and plasmids, there are examples of spacers that match genes elsewhere in the host bacterial chromosome. In Pectobacterium atrosepticum the type I-F CRISPR/Cas system has acquired a self-complementary spacer that perfectly matches a protospacer target in a horizontally acquired island (HAI2 involved in plant pathogenicity. Given the paucity of experimental data about CRISPR/Cas-mediated chromosomal targeting, we examined this process by developing a tightly controlled system. Chromosomal targeting was highly toxic via targeting of DNA and resulted in growth inhibition and cellular filamentation. The toxic phenotype was avoided by mutations in the cas operon, the CRISPR repeats, the protospacer target, and protospacer-adjacent motif (PAM beside the target. Indeed, the natural self-targeting spacer was non-toxic due to a single nucleotide mutation adjacent to the target in the PAM sequence. Furthermore, we show that chromosomal targeting can result in large-scale genomic alterations, including the remodelling or deletion of entire pre-existing pathogenicity islands. These features can be engineered for the targeted deletion of large regions of bacterial chromosomes. In conclusion, in DNA-targeting CRISPR/Cas systems, chromosomal interference is deleterious by causing DNA damage and providing a strong selective pressure for genome alterations, which may have consequences for bacterial evolution and pathogenicity.

  9. Radical remodeling of the Y chromosome in a recent radiation of malaria mosquitoes.

    Science.gov (United States)

    Hall, Andrew Brantley; Papathanos, Philippos-Aris; Sharma, Atashi; Cheng, Changde; Akbari, Omar S; Assour, Lauren; Bergman, Nicholas H; Cagnetti, Alessia; Crisanti, Andrea; Dottorini, Tania; Fiorentini, Elisa; Galizi, Roberto; Hnath, Jonathan; Jiang, Xiaofang; Koren, Sergey; Nolan, Tony; Radune, Diane; Sharakhova, Maria V; Steele, Aaron; Timoshevskiy, Vladimir A; Windbichler, Nikolai; Zhang, Simo; Hahn, Matthew W; Phillippy, Adam M; Emrich, Scott J; Sharakhov, Igor V; Tu, Zhijian Jake; Besansky, Nora J

    2016-04-12

    Y chromosomes control essential male functions in many species, including sex determination and fertility. However, because of obstacles posed by repeat-rich heterochromatin, knowledge of Y chromosome sequences is limited to a handful of model organisms, constraining our understanding of Y biology across the tree of life. Here, we leverage long single-molecule sequencing to determine the content and structure of the nonrecombining Y chromosome of the primary African malaria mosquito, Anopheles gambiae We find that the An. gambiae Y consists almost entirely of a few massively amplified, tandemly arrayed repeats, some of which can recombine with similar repeats on the X chromosome. Sex-specific genome resequencing in a recent species radiation, the An. gambiae complex, revealed rapid sequence turnover within An. gambiae and among species. Exploiting 52 sex-specific An. gambiae RNA-Seq datasets representing all developmental stages, we identified a small repertoire of Y-linked genes that lack X gametologs and are not Y-linked in any other species except An. gambiae, with the notable exception of YG2, a candidate male-determining gene. YG2 is the only gene conserved and exclusive to the Y in all species examined, yet sequence similarity to YG2 is not detectable in the genome of a more distant mosquito relative, suggesting rapid evolution of Y chromosome genes in this highly dynamic genus of malaria vectors. The extensive characterization of the An. gambiae Y provides a long-awaited foundation for studying male mosquito biology, and will inform novel mosquito control strategies based on the manipulation of Y chromosomes. PMID:27035980

  10. The pituitary-thyroid axis set point in women is uninfluenced by X chromosome inactivation pattern? A twin study

    DEFF Research Database (Denmark)

    Brix, Thomas H; Hansen, Pia S; Kyvik, Kirsten O; Hegedüs, Laszlo

    2010-01-01

    The pituitary-thyroid axis (PTA) set point is determined by a combination of genetic and environmental factors. However, despite considerable efforts to characterize the background, the causative genes as well as environmental factors are not well established. Theoretically, as shown for autoimmune...... thyroid disease, the pattern of X chromosome inactivation (XCI) could offer a novel explanation for the observed variability of the PTA set point in women....

  11. Divergent actions of long noncoding RNAs on X-chromosome remodelling in mammals and Drosophila achieve the same end result: dosage compensation

    Indian Academy of Sciences (India)

    Subhash C. Lakhotia

    2015-12-01

    Organisms with heterochromatic sex chromosomes need to compensate for differences in dosages of the sex chromosome-linked genes that have somatic functions. In-depth cytological and subsequent biochemical and molecular studies on dosage compensation started with Mary F. Lyon’s proposal in early 1960s that the Barr body in female mammalian somatic cells represented one of the randomly inactivated and heterochromatinized X chromosomes. In contrast, Drosophila was soon shown to achieve dosage compensation through hypertranscription of single X in male whose chromatin remains more open. Identification of proteins that remodel chromatin either to cause one of the two X chromosomes in somatic cells of very early female mammalian embryos to become condensed and inactive or to remodel the single X in male Drosophila embryos to a more open state for hypertranscription provided important insights into the underlying cellular epigenetic processes. However, the most striking and unexpected discoveries were the identification of long noncoding RNAs (lncRNAs), X- inactive specific transcript (Xist) in mammals and roX1/2 in Drosophila, which were essential for achieving the contrasting chromatin organizations but leading to similar end result in terms of dosage compensation of X-linked genes in females and males. An overview of the processes of X inactivation or hyperactivation in mammals and Drosophila, respectively, and the roles played by Xist, roX1/2 and other lncRNAs in these events is presented.

  12. Chromosome Painting Reveals Asynaptic Full Alignment of Homologs and HIM-8–Dependent Remodeling of X Chromosome Territories during Caenorhabditis elegans Meiosis

    Science.gov (United States)

    Nabeshima, Kentaro; Mlynarczyk-Evans, Susanna; Villeneuve, Anne M.

    2011-01-01

    During early meiotic prophase, a nucleus-wide reorganization leads to sorting of chromosomes into homologous pairs and to establishing associations between homologous chromosomes along their entire lengths. Here, we investigate global features of chromosome organization during this process, using a chromosome painting method in whole-mount Caenorhabditis elegans gonads that enables visualization of whole chromosomes along their entire lengths in the context of preserved 3D nuclear architecture. First, we show that neither spatial proximity of premeiotic chromosome territories nor chromosome-specific timing is a major factor driving homolog pairing. Second, we show that synaptonemal complex-independent associations can support full lengthwise juxtaposition of homologous chromosomes. Third, we reveal a prominent elongation of chromosome territories during meiotic prophase that initiates prior to homolog association and alignment. Mutant analysis indicates that chromosome movement mediated by association of chromosome pairing centers (PCs) with mobile patches of the nuclear envelope (NE)–spanning SUN-1/ZYG-12 protein complexes is not the primary driver of territory elongation. Moreover, we identify new roles for the X chromosome PC (X-PC) and X-PC binding protein HIM-8 in promoting elongation of X chromosome territories, separable from their role(s) in mediating local stabilization of pairing and association of X chromosomes with mobile SUN-1/ZYG-12 patches. Further, we present evidence that HIM-8 functions both at and outside of PCs to mediate chromosome territory elongation. These and other data support a model in which synapsis-independent elongation of chromosome territories, driven by PC binding proteins, enables lengthwise juxtaposition of chromosomes, thereby facilitating assessment of their suitability as potential pairing partners. PMID:21876678

  13. Hypoxia-inducible factor-1 α/platelet derived growth factor axis in HIV-associated pulmonary vascular remodeling

    Directory of Open Access Journals (Sweden)

    Bartolome Sonja

    2011-08-01

    Full Text Available Abstract Background Human immunodeficiency virus (HIV infected patients are at increased risk for the development of pulmonary arterial hypertension (PAH. Recent reports have demonstrated that HIV associated viral proteins induce reactive oxygen species (ROS with resultant endothelial cell dysfunction and related vascular injury. In this study, we explored the impact of HIV protein induced oxidative stress on production of hypoxia inducible factor (HIF-1α and platelet-derived growth factor (PDGF, critical mediators implicated in the pathogenesis of HIV-PAH. Methods The lungs from 4-5 months old HIV-1 transgenic (Tg rats were assessed for the presence of pulmonary vascular remodeling and HIF-1α/PDGF-BB expression in comparison with wild type controls. Human primary pulmonary arterial endothelial cells (HPAEC were treated with HIV-associated proteins in the presence or absence of pretreatment with antioxidants, for 24 hrs followed by estimation of ROS levels and western blot analysis of HIF-1α or PDGF-BB. Results HIV-Tg rats, a model with marked viral protein induced vascular oxidative stress in the absence of active HIV-1 replication demonstrated significant medial thickening of pulmonary vessels and increased right ventricular mass compared to wild-type controls, with increased expression of HIF-1α and PDGF-BB in HIV-Tg rats. The up-regulation of both HIF-1α and PDGF-B chain mRNA in each HIV-Tg rat was directly correlated with an increase in right ventricular/left ventricular+septum ratio. Supporting our in-vivo findings, HPAECs treated with HIV-proteins: Tat and gp120, demonstrated increased ROS and parallel increase of PDGF-BB expression with the maximum induction observed on treatment with R5 type gp-120CM. Pre-treatment of endothelial cells with antioxidants or transfection of cells with HIF-1α small interfering RNA resulted in abrogation of gp-120CM mediated induction of PDGF-BB, therefore, confirming that ROS generation and

  14. Localized remodeling of the Escherichia coli chromosome: the patchwork of segments refractory and tolerant to inversion near the replication terminus.

    Science.gov (United States)

    Guijo, M I; Patte, J; del Mar Campos, M; Louarn, J M; Rebollo, J E

    2001-01-01

    The behavior of chromosomal inversions in Escherichia coli depends upon the region they affect. Regions flanking the replication terminus have been termed nondivisible zones (NDZ) because inversions ending in the region were either deleterious or not feasible. This regional phenomenon is further analyzed here. Thirty segments distributed between 23 and 29 min on the chromosome map have been submitted to an inversion test. Twenty-five segments either became deleterious when inverted or were noninvertible, but five segments tolerated inversion. The involvement of polar replication pause sites in this distribution was investigated. The results suggest that the Tus/pause site system may forbid some inversion events, but that other constraints to inversion, unrelated to this system, exist. Our current model for deleterious inversions is that the segments involved carry polar sequences acting in concert with other polar sequences located outside the segments. The observed patchwork of refractory and tolerant segments supports the existence of several NDZs in the 23- to 29-min region. Microscopic observations revealed that deleterious inversions are associated with high frequencies of abnormal nucleoid structure and distribution. Combined with other information, the data suggest that NDZs participate in the organization of the terminal domain of the nucleoid. PMID:11290700

  15. Caloric restriction-associated remodeling of rat white adipose tissue: effects on the growth hormone/insulin-like growth factor-1 axis, sterol regulatory element binding protein-1, and macrophage infiltration

    OpenAIRE

    Chujo, Yoshikazu; Fujii, Namiki; Okita, Naoyuki; Konishi, Tomokazu; Narita, Takumi; Yamada, Atsushi; Haruyama, Yushi; Tashiro, Kosuke; Chiba, Takuya; Shimokawa, Isao; Higami, Yoshikazu

    2012-01-01

    The role of the growth hormone (GH)-insulin-like growth factor (IGF)-1 axis in the lifelong caloric restriction (CR)-associated remodeling of white adipose tissue (WAT), adipocyte size, and gene expression profiles was explored in this study. We analyzed the WAT morphology of 6–7-month-old wild-type Wistar rats fed ad libitum (WdAL) or subjected to CR (WdCR), and of heterozygous transgenic dwarf rats bearing an anti-sense GH transgene fed ad libitum (TgAL) or subjected to CR (TgCR). Although ...

  16. The WSTF-ISWI chromatin remodeling complex transiently associates with the human inactive X chromosome during late S-phase prior to BRCA1 and γ-H2AX.

    Directory of Open Access Journals (Sweden)

    Ashley E Culver-Cochran

    Full Text Available Replicating the genome prior to each somatic cell division not only requires precise duplication of the genetic information, but also accurately reestablishing the epigenetic signatures that instruct how the genetic material is to be interpreted in the daughter cells. The mammalian inactive X chromosome (Xi, which is faithfully inherited in a silent state in each daughter cell, provides an excellent model of epigenetic regulation. While much is known about the early stages of X chromosome inactivation, much less is understood with regards to retaining the Xi chromatin through somatic cell division. Here we report that the WSTF-ISWI chromatin remodeling complex (WICH associates with the Xi during late S-phase as the Xi DNA is replicated. Elevated levels of WICH at the Xi is restricted to late S-phase and appears before BRCA1 and γ-H2A.X. The sequential appearance of WICH and BRCA1/γ-H2A.X implicate each as performing important but distinct roles in the maturation and maintenance of heterochromatin at the Xi.

  17. Abnormal sex chromosome constitution and longitudinal growth

    DEFF Research Database (Denmark)

    Aksglaede, Lise; Skakkebaek, Niels E; Juul, Anders

    2008-01-01

    Growth is a highly complex process regulated by the interaction between sex steroids and the GH IGF-axis. However, other factors such as sex chromosome-related genes play independent roles.......Growth is a highly complex process regulated by the interaction between sex steroids and the GH IGF-axis. However, other factors such as sex chromosome-related genes play independent roles....

  18. Immunoregulation of bone remodelling

    Science.gov (United States)

    Singh, Ajai; Mehdi, Abbass A; Srivastava, Rajeshwer N; Verma, Nar Singh

    2012-01-01

    Remodeling, a continuous physiological process maintains the strength of the bones, which maintains a delicate balance between bone formation and resorption process. This review gives an insight to the complex interaction and correlation between the bone remodeling and the corresponding changes in host immunological environment and also summarises the most recent developments occuring in the understanding of this complex field. T cells, both directly and indirectly increase the expression of receptor activator of nuclear factor kB ligand (RANKL); a vital step in the activation of osteoclasts, thus positively regulates the osteoclastogenesis. Though various cytokines, chemikines, transcription factors and co-stimulatory molecules are shared by both skeletal and immune systems, but researches are being conducted to establish and analyse their role and / or control on this complex but vital process. The understanding of this part of research may open new horizons in the management of inflammatory and autoimmune diseases, resulting into bone loss and that of osteoporosis also. PMID:22837895

  19. Restenosis and remodeling

    International Nuclear Information System (INIS)

    Percutaneous Transluminal Coronary Angioplasty (PTCA) remains limited by restenosis that occurs in 30 to 50% of patients with coronary artery disease. During the last decade, numerous agents have been used to prevent restenosis. Despite positive results in animal models, no pharmacological therapy has been found to significantly decrease the risk of restenosis in humans. These discrepancies between animal models and clinical situation were probably related to an incomplete understanding of the mechanism of restenosis. Neointimal thickening occurs in response to experimental arterial injury with a balloon catheter. Neointimal formation involves different steps: smooth muscle cell activation, proliferation and migration, and the production of extracellular matrix. The factors that control neointimal hyperplasia include growth factors humoral factors and mechanical factors. Arterial remodeling also plays a major role in the restenosis process. Studies performed in animal and human subjects have established the potentials for 'constrictive remodeling' to reduce the post-angioplasty vessel area, thereby indirectly narrowing the vessel lumen and thus contributing to restenosis. The reduction of restenosis rate in patients with intracoronary stent implantation has been attributed to the preventive effect of stent itself for this negative remodeling. In addition to these mechanism for restenosis, intraluminal or intra-plaque thrombus formation, reendothelialization and apoptosis theories have been introduced and confirmed at least in part

  20. Epigenetic remodelling and dysregulation of DLGAP4 is linked with early-onset cerebellar ataxia

    DEFF Research Database (Denmark)

    Minocherhomji, Sheroy; Hansen, Claus; Kim, Hyung-Goo;

    2014-01-01

    Genome instability, epigenetic remodelling and structural chromosomal rearrangements are hallmarks of cancer. However, the coordinated epigenetic effects of constitutional chromosomal rearrangements that disrupt genes associated with congenital neurodevelopmental diseases are poorly understood....... To understand the genetic-epigenetic interplay at breakpoints of chromosomal translocations disrupting CG-rich loci, we quantified epigenetic modifications at DLGAP4 (SAPAP4), a key post-synaptic density 95 (PSD95) associated gene, truncated by the chromosome translocation t(8;20)(p12;q11.23), co......-segregating with cerebellar ataxia in a five-generation family. We report significant epigenetic remodelling of the DLGAP4 locus triggered by the t(8;20)(p12;q11.23) translocation and leading to dysregulation of DLGAP4 expression in affected carriers. Disruption of DLGAP4 results in monoallelic hypermethylation...

  1. No-Regrets Remodeling, 2nd Edition

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-12-01

    No-Regrets Remodeling, sponsored by Oak Ridge National Laboratory, is an informative publication that walks homeowners and/or remodelers through various home remodeling projects. In addition to remodeling information, the publication provides instruction on how to incorporate energy efficiency into the remodeling process. The goal of the publication is to improve homeowner satisfaction after completing a remodeling project and to provide the homeowner with a home that saves energy and is comfortable and healthy.

  2. Chromosomal aberration

    International Nuclear Information System (INIS)

    Chromosomal aberrations are classified into two types, chromosome-type and chromatid-type. Chromosom-type aberrations include terminal deletion, dicentric, ring and interstitial deletion, and chromatid-type aberrations include achromatic lesion, chromatid deletion, isochromatid deletion and chromatid exchange. Clastogens which induce chromosomal aberration are divided into ''S-dependent'' agents and ''S-independent''. It might mean whether they can induce double strand breaks independent of the S phase or not. Double strand breaks may be the ultimate lesions to induce chromosomal aberrations. Caffeine added even in the G2 phase appeared to modify the frequency of chromatid aberrations induced by X-rays and mitomycin C. Those might suggest that the G2 phase involves in the chromatid aberration formation. The double strand breaks might be repaired by ''G2 repair system'', the error of which might yield breakage types of chromatid aberrations and the by-pass of which might yield chromatid exchanges. Chromosome-type aberrations might be formed in the G1 phase. (author)

  3. Synthetic chromosomes.

    Science.gov (United States)

    Schindler, Daniel; Waldminghaus, Torsten

    2015-11-01

    What a living organism looks like and how it works and what are its components-all this is encoded on DNA, the genetic blueprint. Consequently, the way to change an organism is to change its genetic information. Since the first pieces of recombinant DNA have been used to transform cells in the 1970s, this approach has been enormously extended. Bigger and bigger parts of the genetic information have been exchanged or added over the years. Now we are at a point where the construction of entire chromosomes becomes a reachable goal and first examples appear. This development leads to fundamental new questions, for example, about what is possible and desirable to build or what construction rules one needs to follow when building synthetic chromosomes. Here we review the recent progress in the field, discuss current challenges and speculate on the appearance of future synthetic chromosomes. PMID:26111960

  4. Chromosome Microarray.

    Science.gov (United States)

    Anderson, Sharon

    2016-01-01

    Over the last half century, knowledge about genetics, genetic testing, and its complexity has flourished. Completion of the Human Genome Project provided a foundation upon which the accuracy of genetics, genomics, and integration of bioinformatics knowledge and testing has grown exponentially. What is lagging, however, are efforts to reach and engage nurses about this rapidly changing field. The purpose of this article is to familiarize nurses with several frequently ordered genetic tests including chromosomes and fluorescence in situ hybridization followed by a comprehensive review of chromosome microarray. It shares the complexity of microarray including how testing is performed and results analyzed. A case report demonstrates how this technology is applied in clinical practice and reveals benefits and limitations of this scientific and bioinformatics genetic technology. Clinical implications for maternal-child nurses across practice levels are discussed. PMID:27276104

  5. Chromosomes. A comprehensive Xist interactome reveals cohesin repulsion and an RNA-directed chromosome conformation.

    Science.gov (United States)

    Minajigi, Anand; Froberg, John E; Wei, Chunyao; Sunwoo, Hongjae; Kesner, Barry; Colognori, David; Lessing, Derek; Payer, Bernhard; Boukhali, Myriam; Haas, Wilhelm; Lee, Jeannie T

    2015-07-17

    The inactive X chromosome (Xi) serves as a model to understand gene silencing on a global scale. Here, we perform "identification of direct RNA interacting proteins" (iDRiP) to isolate a comprehensive protein interactome for Xist, an RNA required for Xi silencing. We discover multiple classes of interactors-including cohesins, condensins, topoisomerases, RNA helicases, chromatin remodelers, and modifiers-that synergistically repress Xi transcription. Inhibiting two or three interactors destabilizes silencing. Although Xist attracts some interactors, it repels architectural factors. Xist evicts cohesins from the Xi and directs an Xi-specific chromosome conformation. Upon deleting Xist, the Xi acquires the cohesin-binding and chromosomal architecture of the active X. Our study unveils many layers of Xi repression and demonstrates a central role for RNA in the topological organization of mammalian chromosomes. PMID:26089354

  6. Neural remodeling in retinal degeneration.

    Science.gov (United States)

    Marc, Robert E; Jones, Bryan W; Watt, Carl B; Strettoi, Enrica

    2003-09-01

    Mammalian retinal degenerations initiated by gene defects in rods, cones or the retinal pigmented epithelium (RPE) often trigger loss of the sensory retina, effectively leaving the neural retina deafferented. The neural retina responds to this challenge by remodeling, first by subtle changes in neuronal structure and later by large-scale reorganization. Retinal degenerations in the mammalian retina generally progress through three phases. Phase 1 initiates with expression of a primary insult, followed by phase 2 photoreceptor death that ablates the sensory retina via initial photoreceptor stress, phenotype deconstruction, irreversible stress and cell death, including bystander effects or loss of trophic support. The loss of cones heralds phase 3: a protracted period of global remodeling of the remnant neural retina. Remodeling resembles the responses of many CNS assemblies to deafferentation or trauma, and includes neuronal cell death, neuronal and glial migration, elaboration of new neurites and synapses, rewiring of retinal circuits, glial hypertrophy and the evolution of a fibrotic glial seal that isolates the remnant neural retina from the surviving RPE and choroid. In early phase 2, stressed photoreceptors sprout anomalous neurites that often reach the inner plexiform and ganglion cell layers. As death of rods and cones progresses, bipolar and horizontal cells are deafferented and retract most of their dendrites. Horizontal cells develop anomalous axonal processes and dendritic stalks that enter the inner plexiform layer. Dendrite truncation in rod bipolar cells is accompanied by revision of their macromolecular phenotype, including the loss of functioning mGluR6 transduction. After ablation of the sensory retina, Müller cells increase intermediate filament synthesis, forming a dense fibrotic layer in the remnant subretinal space. This layer invests the remnant retina and seals it from access via the choroidal route. Evidence of bipolar cell death begins in

  7. Chromatin remodeling, development and disease

    International Nuclear Information System (INIS)

    Development is a stepwise process in which multi-potent progenitor cells undergo lineage commitment, differentiation, proliferation and maturation to produce mature cells with restricted developmental potentials. This process is directed by spatiotemporally distinct gene expression programs that allow cells to stringently orchestrate intricate transcriptional activation or silencing events. In eukaryotes, chromatin structure contributes to developmental progression as a blueprint for coordinated gene expression by actively participating in the regulation of gene expression. Changes in higher order chromatin structure or covalent modification of its components are considered to be critical events in dictating lineage-specific gene expression during development. Mammalian cells utilize multi-subunit nuclear complexes to alter chromatin structure. Histone-modifying complex catalyzes covalent modifications of histone tails including acetylation, methylation, phosphorylation and ubiquitination. ATP-dependent chromatin remodeling complex, which disrupts histone-DNA contacts and induces nucleosome mobilization, requires energy from ATP hydrolysis for its catalytic activity. Here, we discuss the diverse functions of ATP-dependent chromatin remodeling complexes during mammalian development. In particular, the roles of these complexes during embryonic and hematopoietic development are reviewed in depth. In addition, pathological conditions such as tumor development that are induced by mutation of several key subunits of the chromatin remodeling complex are discussed, together with possible mechanisms that underlie tumor suppression by the complex

  8. Vascular Remodeling in Experimental Hypertension

    Directory of Open Access Journals (Sweden)

    Norma R. Risler

    2005-01-01

    Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

  9. Cardiac Remodeling After Atrial Fibrillation Ablation

    Directory of Open Access Journals (Sweden)

    Li-Wei Lo, MD; Shih-Ann Chen, MD

    2013-06-01

    Full Text Available Radiofrequency catheter ablation procedures are considered a reasonable option for patients with symptomatic, drug refractory atrial fibrillation (AF. Ablation procedures have been reported to effectively restore sinus rhythm and provide long-term relief of symptoms. Both electrical and structural remodeling occurs with AF. A reversal of the electrical remodeling develops within 1 week after restoration to sinus rhythm following the catheter ablation. The recovery rate is faster in the right atrium than the left atrium. Reverse structural remodeling takes longer and is still present 2 to 4 months after restoration of sinus rhythm. The left atrial transport function also improves after successful catheter ablation of AF. Left atrial strain surveys from echocardiography are able to identify patients who respond to catheter ablation with significant reverse remodeling after ablation. Pre-procedural delayed enhancement magnetic resonance imaging is also able to determine the degree of atrial fibrosis and is another tool to predict the reverse remodeling after ablation. The remodeling process is complex if recurrence develops after ablation. Recent evidence shows that a combined reverse electrical and structural remodeling occurs after ablation of chronic AF when recurrence is paroxysmal AF. Progressive electrical remodeling without any structural remodeling develops in those with recurrence involving chronic AF. Whether progressive atrial remodeling is the cause or consequence during the recurrence of AF remains obscure and requires further study.

  10. Mitotic chromosome structure

    International Nuclear Information System (INIS)

    Mounting evidence is compiling linking the physical organizational structure of chromosomes and the nuclear structure to biological function. At the base of the physical organizational structure of both is the concept of loop formation. This implies that physical proximity within chromosomes is provided for otherwise distal genomic regions and thus hierarchically organizing the chromosomes. Together with entropy many experimental observations can be explained with these two concepts. Among the observations that can be explained are the measured physical extent of the chromosomes, their shape, mechanical behavior, the segregation into territories (chromosomal and territories within chromosomes), the results from chromosome conformation capture experiments, as well as linking gene expression to structural organization.

  11. Cellular and Molecular Mechanisms of Bone Remodeling*

    OpenAIRE

    Raggatt, Liza J; Partridge, Nicola C

    2010-01-01

    Physiological bone remodeling is a highly coordinated process responsible for bone resorption and formation and is necessary to repair damaged bone and to maintain mineral homeostasis. In addition to the traditional bone cells (osteoclasts, osteoblasts, and osteocytes) that are necessary for bone remodeling, several immune cells have also been implicated in bone disease. This minireview discusses physiological bone remodeling, outlining the traditional bone biology dogma in light of emerging ...

  12. Cardiac electrical remodeling in health and disease

    OpenAIRE

    Cutler, Michael J.; Jeyaraj, Darwin; Rosenbaum, David S.

    2011-01-01

    Electrical remodeling of the heart occurs in response to both functional (i.e. altered electrical activation) and structural (i.e. heart failure, myocardial infarction, etc.) stressors. These electrophysiological changes produce a substrate that is vulnerable to malignant ventricular arrhythmias. Understanding the cellular and molecular mechanisms of electrical remodeling is important in elucidating potential therapeutic targets designed to alter maladaptive electrical remodeling. For example...

  13. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J;

    1983-01-01

    A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were...... unbalanced chromosome abnormality in group A (women with elevated risk) is significantly higher than in group B + C (women without elevated risk) (relative risk 2.4). Women with a known familial translocation and women 40 years or more have a relative risk of 5.7 of having an unbalanced chromosome......The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...

  14. A gene-centric study of common carotid artery remodelling

    Science.gov (United States)

    Harrison, Seamus C.; Zabaneh, Delilah; Asselbergs, Folkert W.; Drenos, Fotios; Jones, Gregory T.; Shah, Sonia; Gertow, Karl; Sennblad, Bengt; Strawbridge, Rona J.; Gigante, Bruna; Holewijn, Suzanne; De Graaf, Jacqueline; Vermeulen, Sita; Folkersen, Lasse; van Rij, Andre M.; Baldassarre, Damiano; Veglia, Fabrizio; Talmud, Philippa J.; Deanfield, John E.; Agu, Obi; Kivimaki, Mika; Kumari, Meena; Bown, Matthew J.; Nyyssönen, Kristiina; Rauramaa, Rainer; Smit, Andries J.; Franco-Cereceda, Anders; Giral, Philippe; Mannarino, Elmo; Silveira, Angela; Syvänen, Ann-Christine; de Borst, Gert J.; van der Graaf, Yolanda; de Faire, Ulf; Baas, Annette F.; Blankensteijn, Jan D.; Wareham, Nicholas J.; Fowkes, Gerry; Tzoulaki, Ionna; Price, Jacqueline F.; Tremoli, Elena; Hingorani, Aroon D.; Eriksson, Per; Hamsten, Anders; Humphries, Steve E.

    2013-01-01

    Background Expansive remodelling is the process of compensatory arterial enlargement in response to atherosclerotic stimuli. The genetic determinants of this process are poorly characterized. Methods Genetic association analyses of inter-adventitial common carotid artery diameter (ICCAD) in the IMPROVE study (n = 3427) using the Illumina 200k Metabochip was performed. Single nucleotide polymorphisms (SNPs) that met array-wide significance were taken forward for analysis in three further studies (n = 5704), and tested for association with Abdominal Aortic Aneurysm (AAA). Results rs3768445 on Chromosome 1q24.3, in a cluster of protein coding genes (DNM3, PIGC, C1orf105) was associated with larger ICCAD in the IMPROVE study. For each copy of the rare allele carried, ICCAD was on average 0.13 mm greater (95% CI 0.08–0.18 mm, P = 8.2 × 10−8). A proxy SNP (rs4916251, R2 = 0.99) did not, however, show association with ICCAD in three follow-up studies (P for replication = 0.29). There was evidence of interaction between carotid intima-media thickness (CIMT) and rs4916251 on ICCAD in two of the cohorts studies suggesting that it plays a role in the remodelling response to atherosclerosis. In meta-analysis of 5 case–control studies pooling data from 5007 cases and 43,630 controls, rs4916251 was associated with presence of AAA 1.10, 95% CI 1.03–1.17, p = 2.8 × 10−3, I2 = 18.8, Q = 0.30). A proxy SNP, rs4916251 was also associated with increased expression of PIGC in aortic tissue, suggesting that this may the mechanism by which this locus affects vascular remodelling. Conclusions Common variation at 1q24.3 is associated with expansive vascular remodelling and risk of AAA. These findings support a hypothesis that pathways involved in systemic vascular remodelling play a role in AAA development. PMID:23246012

  15. A cohesin-based structural platform supporting homologous chromosome pairing in meiosis.

    Science.gov (United States)

    Ding, Da-Qiao; Haraguchi, Tokuko; Hiraoka, Yasushi

    2016-08-01

    The pairing and recombination of homologous chromosomes during the meiotic prophase is necessary for the accurate segregation of chromosomes in meiosis. However, the mechanism by which homologous chromosomes achieve this pairing has remained an open question. Meiotic cohesins have been shown to affect chromatin compaction; however, the impact of meiotic cohesins on homologous pairing and the fine structures of cohesion-based chromatin remain to be determined. A recent report using live-cell imaging and super-resolution microscopy demonstrated that the lack of meiotic cohesins alters the chromosome axis structures and impairs the pairing of homologous chromosomes. These results suggest that meiotic cohesin-based chromosome axis structures are crucial for the pairing of homologous chromosomes. PMID:26856595

  16. Remodeling dan Repairing Vaskular pada Nefropati Hipertensif

    OpenAIRE

    Rasyid, Haerani; Wijaya, Johnson; Bakri, Syakib

    2011-01-01

    Latar Belakang: Ketidakseimbangan proses remodeling dan repairing vaskular diduga berperan penting pada kekakuan dan ketebalan vaskular yang akhirnya menyebabkan komplikasi hipertensi. Petanda dini komplikasi hipertensi pada ginjal adalah adanya mikroalbuminuria (MA). Tujuan Penelitian: Untuk mengetahui perbedaan konsentrasi TGF-??1 (sebagai petanda remodeling) dan VEGFR-2 (sebagai petanda repairing) pada subyek normotensi, hipertensi normoalbuminuria (NA) dan hipertensi MA. Metode: P...

  17. Multiscale Simulation of Protein Mediated Membrane Remodeling

    OpenAIRE

    Ayton, Gary S.; Voth, Gregory A.

    2009-01-01

    Proteins interacting with membranes can result in substantial membrane deformations and curvatures. This effect is known in its broadest terms as membrane remodeling. This review article will survey current multiscale simulation methodologies that have been employed to examine protein-mediated membrane remodeling.

  18. Nucleosome dynamics during chromatin remodeling in vivo.

    Science.gov (United States)

    Ramachandran, Srinivas; Henikoff, Steven

    2016-01-01

    Precise positioning of nucleosomes around regulatory sites is achieved by the action of chromatin remodelers, which use the energy of ATP to slide, evict or change the composition of nucleosomes. Chromatin remodelers act to bind nucleosomes, disrupt histone-DNA interactions and translocate the DNA around the histone core to reposition nucleosomes. Hence, remodeling is expected to involve nucleosomal intermediates with a structural organization that is distinct from intact nucleosomes. We describe the identification of a partially unwrapped nucleosome structure using methods that map histone-DNA contacts genome-wide. This alternative nucleosome structure is likely formed as an intermediate or by-product during nucleosome remodeling by the RSC complex. Identification of the loss of histone-DNA contacts during chromatin remodeling by RSC in vivo has implications for the regulation of transcriptional initiation. PMID:26933790

  19. Chromosome painting in plants.

    NARCIS (Netherlands)

    Schubert, I.; Fransz, P.F.; Fuchs, J.; Jong, de J.H.

    2001-01-01

    The current 'state-of-art' as to chromosome painting in plants is reviewed. We define different situations described as painting so far: i) Genomic in situ hybridisation (GISH) with total genomic DNA to distinguish alien chromosomes on the basis of divergent dispersed repeats, ii) 'Chromosomal in si

  20. Thyroid Hormone and Vascular Remodeling.

    Science.gov (United States)

    Ichiki, Toshihiro

    2016-03-01

    Both hyperthyroidism and hypothyroidism affect the cardiovascular system. Hypothyroidism is known to be associated with enhanced atherosclerosis and ischemic heart diseases. The accelerated atherosclerosis in the hypothyroid state has been traditionally ascribed to atherogenic lipid profile, diastolic hypertension, and impaired endothelial function. However, recent studies indicate that thyroid hormone has direct anti-atherosclerotic effects, such as production of nitric oxide and suppression of smooth muscle cell proliferation. These data suggest that thyroid hormone inhibits atherogenesis through direct effects on the vasculature as well as modification of risk factors for atherosclerosis. This review summarizes the basic and clinical studies on the role of thyroid hormone in vascular remodeling. The possible application of thyroid hormone mimetics to the therapy of hypercholesterolemia and atherosclerosis is also discussed. PMID:26558400

  1. Obesity and carotid artery remodeling

    DEFF Research Database (Denmark)

    Kozakova, M; Palombo, C; Morizzo, C;

    2015-01-01

    BACKGROUND/OBJECTIVE: The present study tested the hypothesis that obesity-related changes in carotid intima-media thickness (IMT) might represent not only preclinical atherosclerosis but an adaptive remodeling meant to preserve circumferential wall stress (CWS) in altered hemodynamic conditions...... and CCA LD (266 healthy subjects with wide range of body weight (24-159 kg)); (B) longitudinal associations between CCA LD and 3-year IMT progression rate (ΔIMT; 571 healthy non-obese subjects without increased cardiovascular (CV) risk); (C) the impact of obesity on CCA geometry and CWS (88 obese...... subjects without CV complications and 88 non-obese subjects matched for gender and age). RESULTS: CCA LD was independently associated with SV that was determined by body size. In the longitudinal study, baseline LD was an independent determinant of ΔIMT, and ΔIMT of subjects in the highest LD quartile was...

  2. Triple axis spectrometers

    International Nuclear Information System (INIS)

    Conventional triple-axis neutron spectroscopy was developed by Brockhouse over thirty years ago' and remains today a versatile and powerful tool for probing the dynamics of condensed matter. The original design of the triple axis spectrometer is technically simple and probes momentum and energy space on a point-by-point basis. This ability to systematically probe the scattering function in a way which only requires a few angles to be moved under computer control and where the observed data in general can be analysed using a pencil and graph paper or a simple fitting routine, has been essential for the success of the method. These constraints were quite reasonable at the time the technique was developed. Advances in computer based data acquisition, neutron beam optics, and position sensitive area detectors have been gradually implemented on many triple axis spectrometer spectrometers, but the full potential of this has not been fully exploited yet. Further improvement in terms of efficiency (beyond point by point inspection) and increased sensitivity (use of focusing optics whenever the problem allows it) could easily be up to a factor of 10-20 over present instruments for many problems at a cost which is negligible compared to that of increasing the flux of the source. The real cost will be in complexity - finding the optimal set-up for a given scan and interpreting the data as the they are taken. On-line transformation of the data for an appropriate display in Q, ω space and analysis tools will be equally important for this task, and the success of these new ideas will crucially depend on how well we solve these problems. (author)

  3. Cholinergic Regulation of Airway Inflammation and Remodelling

    Directory of Open Access Journals (Sweden)

    Saeed Kolahian

    2012-01-01

    Full Text Available Acetylcholine is the predominant parasympathetic neurotransmitter in the airways that regulates bronchoconstriction and mucus secretion. Recent findings suggest that acetylcholine regulates additional functions in the airways, including inflammation and remodelling during inflammatory airway diseases. Moreover, it has become apparent that acetylcholine is synthesized by nonneuronal cells and tissues, including inflammatory cells and structural cells. In this paper, we will discuss the regulatory role of acetylcholine in inflammation and remodelling in which we will focus on the role of the airway smooth muscle cell as a target cell for acetylcholine that modulates inflammation and remodelling during respiratory diseases such as asthma and COPD.

  4. A novel chromosome segregation mechanism during female meiosis.

    Science.gov (United States)

    McNally, Karen Perry; Panzica, Michelle T; Kim, Taekyung; Cortes, Daniel B; McNally, Francis J

    2016-08-15

    In a wide range of eukaryotes, chromosome segregation occurs through anaphase A, in which chromosomes move toward stationary spindle poles, anaphase B, in which chromosomes move at the same velocity as outwardly moving spindle poles, or both. In contrast, Caenorhabditis elegans female meiotic spindles initially shorten in the pole-to-pole axis such that spindle poles contact the outer kinetochore before the start of anaphase chromosome separation. Once the spindle pole-to-kinetochore contact has been made, the homologues of a 4-μm-long bivalent begin to separate. The spindle shortens an additional 0.5 μm until the chromosomes are embedded in the spindle poles. Chromosomes then separate at the same velocity as the spindle poles in an anaphase B-like movement. We conclude that the majority of meiotic chromosome movement is caused by shortening of the spindle to bring poles in contact with the chromosomes, followed by separation of chromosome-bound poles by outward sliding. PMID:27335123

  5. Chimpanzee chromosome 12 is homologous to human chromosome 2q

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Most of the 46 human chromosomes find their counterparts in the 48 chimpanzee chromosomes except for chromosome 2 which has been hypothesized to have been derived from a centric fusion of two chimpanzee acrocentric chromosomes. These two chromosomes correspond to the human chromosomes 2p and 2g. This conclusion is based primarily on chromosome banding techniques, and the somatic cell hybridization technique has also been used. (HLW)

  6. Preferred axis in cosmology

    CERN Document Server

    Zhao, Wen

    2016-01-01

    The foundation of modern cosmology relies on the so-called cosmological principle which states an homogeneous and isotropic distribution of matter in the universe on large scales. However, recent observations, such as the temperature anisotropy of the cosmic microwave background (CMB) radiation, the motion of galaxies in the universe, the polarization of quasars and the acceleration of the cosmic expansion, indicate preferred directions in the sky. If these directions have a cosmological origin, the cosmological principle would be violated, and modern cosmology should be reconsidered. In this paper, by considering the preferred axis in the CMB parity violation, we find that it coincides with the preferred axes in CMB quadrupole and CMB octopole, and they all align with the direction of the CMB kinematic dipole. In addition, the preferred directions in the velocity flows, quasar alignment, anisotropy of the cosmic acceleration, the handedness of spiral galaxies, and the angular distribution of the fine-structu...

  7. Maxillary Mucocele with Orbital Floor Remodelling

    OpenAIRE

    Tahrina Salam; Maryam Zamani; Jane Olver

    2012-01-01

    A 79-year-old man presents with signs of an orbital mass. A CT scan revealed a large maxillary mucocele eroding through the orbital floor. Surgical drainage of the mucocele and conservative postoperative care, returned all ophthalmic signs to normal and bony remodelling of the orbital floor was demonstrated. Maxillary mucoceles should be assessed by both ENT and Ophthalmic surgeons. Postoperative remodelling of the orbital floor can be illustrated with serial CT Scans.

  8. Dynamics of the ethanolamine glycerophospholipid remodeling network.

    Directory of Open Access Journals (Sweden)

    Lu Zhang

    Full Text Available Acyl chain remodeling in lipids is a critical biochemical process that plays a central role in disease. However, remodeling remains poorly understood, despite massive increases in lipidomic data. In this work, we determine the dynamic network of ethanolamine glycerophospholipid (PE remodeling, using data from pulse-chase experiments and a novel bioinformatic network inference approach. The model uses a set of ordinary differential equations based on the assumptions that (1 sn1 and sn2 acyl positions are independently remodeled; (2 remodeling reaction rates are constant over time; and (3 acyl donor concentrations are constant. We use a novel fast and accurate two-step algorithm to automatically infer model parameters and their values. This is the first such method applicable to dynamic phospholipid lipidomic data. Our inference procedure closely fits experimental measurements and shows strong cross-validation across six independent experiments with distinct deuterium-labeled PE precursors, demonstrating the validity of our assumptions. In contrast, fits of randomized data or fits using random model parameters are worse. A key outcome is that we are able to robustly distinguish deacylation and reacylation kinetics of individual acyl chain types at the sn1 and sn2 positions, explaining the established prevalence of saturated and unsaturated chains in the respective positions. The present study thus demonstrates that dynamic acyl chain remodeling processes can be reliably determined from dynamic lipidomic data.

  9. Diagnostic tools assessing airway remodelling in asthma.

    Science.gov (United States)

    Manso, L; Reche, M; Padial, M A; Valbuena, T; Pascual, C

    2012-01-01

    Asthma is an inflammatory disease of the lower airways characterised by the presence of airway inflammation, reversible airflow obstruction and airway hyperresponsiveness and alterations on the normal structure of the airways, known as remodelling. Remodelling is characterised by the presence of metaplasia of mucous glands, thickening of the lamina reticularis, increased angiogenesis, subepithelial fibrosis and smooth muscle hypertrophy/hyperplasia. Several techniques are being optimised at present to achieve a suitable diagnosis for remodelling. Diagnostic tools could be divided into two groups, namely invasive and non-invasive methods. Invasive techniques bring us information about bronchial structural alterations, obtaining this information directly from pathological tissue, and permit measure histological modification placed in bronchi layers as well as inflammatory and fibrotic cell infiltration. Non-invasive techniques were developed to reduce invasive methods disadvantages and measure airway remodelling-related markers such as cytokines, inflammatory mediators and others. An exhaustive review of diagnostic tools used to analyse airway remodelling in asthma, including the most useful and usually employed methods, as well as the principal advantages and disadvantages of each of them, bring us concrete and summarised information about all techniques used to evaluate alterations on the structure of the airways. A deep knowledge of these diagnostic tools will make an early diagnosis of airway remodelling possible and, probably, early diagnosis will play an important role in the near future of asthma. PMID:22236733

  10. Immunologic and inflammatory mechanisms that drive asthma progression to remodeling

    OpenAIRE

    Broide, David H.

    2008-01-01

    Although histologic features of airway remodeling have been well characterized in asthma, the immunologic and inflammatory mechanisms that drive progression of asthma to remodeling are still incompletely understood. Conceptually, airway remodeling may be due to persistent inflammation and/or aberrant tissue repair mechanisms. It is likely that several immune and inflammatory cell types and mediators are involved in mediating airway remodeling. In addition, different features of airway remodel...

  11. Cardiac remodelling and RAS inhibition.

    Science.gov (United States)

    Ferrario, Carlos M

    2016-06-01

    Risk factors such as hypertension and diabetes are known to augment the activity and tissue expression of angiotensin II (Ang II), the major effector peptide of the renin-angiotensin system (RAS). Overstimulation of the RAS has been implicated in a chain of events that contribute to the pathogenesis of cardiovascular (CV) disease, including the development of cardiac remodelling. This chain of events has been termed the CV continuum. The concept of CV disease existing as a continuum was first proposed in 1991 and it is believed that intervention at any point within the continuum can modify disease progression. Treatment with antihypertensive agents may result in regression of left ventricular hypertrophy, with different drug classes exhibiting different degrees of efficacy. The greatest decrease in left ventricular mass is observed following treatment with angiotensin converting enzyme inhibitors (ACE-Is), which inhibit Ang II formation. Although ACE-Is and angiotensin receptor blockers (ARBs) provide significant benefits in terms of CV events and stroke, mortality remains high. This is partly due to a failure to completely suppress the RAS, and, as our knowledge has increased, an escape phenomenon has been proposed whereby the human sequence of the 12 amino acid substrate angiotensin-(1-12) is converted to Ang II by the mast cell protease, chymase. Angiotensin-(1-12) is abundant in a wide range of organs and has been shown to increase blood pressure in animal models, an effect abolished by the presence of ACE-Is or ARBs. This review explores the CV continuum, in addition to examining the influence of the RAS. We also consider novel pathways within the RAS and how new therapeutic approaches that target this are required to further reduce Ang II formation, and so provide patients with additional benefits from a more complete blockade of the RAS. PMID:27105891

  12. Observations of super early left ventricular remodeling experimental myocardial infarction

    International Nuclear Information System (INIS)

    , the animals were euthanized and their hearts were examined for pathology. SPECT reconstruction parameters: Filter; Butterworth; cutoff 0.35 and order 5: filtered backprojection. Images: short axis, horizontal and vertical long axis. Data analysis: Quantitative analysis: Quantitative Gated SPECT (QGS) software was used for calculating the end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) Data from 16 animals was used. Qualitative analysis was used to assess shape, size of entire left ventricle, and wall motion which data was from 15 dogs. Echocardiography: HP5500 color Doppler ultrasonography diagnosis system with 12 MHz was used for echocardiography. EDV, ESV and EF were calculated by Simpson's method. Statistics analysis: SPSS statistics software was used for all quantitative data analysis. Results: A typical defect with complete absence of wall motion was found at the apex in all dogs (GA and GB) after LAD ligation, beginning with the first acquisition. Post-operatively, EDV and ESV significantly increased compared with pre-operation values. EF significantly decreased post-operatively. The table below shows quantitative data obtained at the earliest time after ligation. EDV and ESV continued to increase during the 6 hours post-operatively, while EF was just the opposite, decreasing with time. Using continuous gated myocardial imaging, reperfusion was found in 10 dogs (62.5%) on the apex area at 1-3 hours after the defect was originally visualized, when a thinning wall could be seen on the apex defect area. By visual analysis we found structural characteristics of left ventricular remodeling, including infarct expansion with thinning (14/15 animals), lengthening (15/15), regional enlargement (9/15) and distortion (11/15). We also found remodeling of non-infarcted myocardium, including thickening (12/15) and lengthening (13/15) as well as global distortion of shape (15/15) and global ventricular dilatation (14/15). Statistical analysis

  13. Plant sex chromosome evolution.

    Science.gov (United States)

    Charlesworth, Deborah

    2013-01-01

    It is now well established that plants have an important place in studies of sex chromosome evolution because of the repeated independent evolution of separate sexes and sex chromosomes. There has been considerable recent progress in studying plant sex chromosomes. In this review, I focus on how these recent studies have helped clarify or answer several important questions about sex chromosome evolution, and I shall also try to clarify some common misconceptions. I also outline future work that will be needed to make further progress, including testing some important ideas by genetic, molecular, and developmental approaches. Systems with different ages can clearly help show the time course of events during changes from an ancestral co-sexual state (hermaphroditism or monoecy), and I will also explain how different questions can be studied in lineages whose dioecy or sex chromosomes evolved at different times in the past. PMID:23125359

  14. A fly's view of neuronal remodeling.

    Science.gov (United States)

    Yaniv, Shiri P; Schuldiner, Oren

    2016-09-01

    Developmental neuronal remodeling is a crucial step in sculpting the final and mature brain connectivity in both vertebrates and invertebrates. Remodeling includes degenerative events, such as neurite pruning, that may be followed by regeneration to form novel connections during normal development. Drosophila provides an excellent model to study both steps of remodeling since its nervous system undergoes massive and stereotypic remodeling during metamorphosis. Although pruning has been widely studied, our knowledge of the molecular and cellular mechanisms is far from complete. Our understanding of the processes underlying regrowth is even more fragmentary. In this review, we discuss recent progress by focusing on three groups of neurons that undergo stereotypic pruning and regrowth during metamorphosis, the mushroom body γ neurons, the dendritic arborization neurons and the crustacean cardioactive peptide peptidergic neurons. By comparing and contrasting the mechanisms involved in remodeling of these three neuronal types, we highlight the common themes and differences as well as raise key questions for future investigation in the field. WIREs Dev Biol 2016, 5:618-635. doi: 10.1002/wdev.241 For further resources related to this article, please visit the WIREs website. PMID:27351747

  15. Vibrio chromosomes share common history

    OpenAIRE

    Gevers Dirk; Chang Sarah; Chang LeeAnn; Kirkup Benjamin C; Polz Martin F

    2010-01-01

    Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II) were identified from 19 sequenced Vibrionales genomes ...

  16. Sequential cloning of chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Lacks, S.A.

    1991-12-31

    A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  17. Biomechanical Remodeling of the Diabetic Gastrointestinal Tract

    DEFF Research Database (Denmark)

    Zhao, Jingbo; Liao, Donghua; Yang, Jian;

    2010-01-01

    several years, several studies demonstrated that experimental diabetes induces GI morphological and biomechanical remodeling. Following the development of diabetes, the GI wall becomes thicker and the stiffness of the GI wall increases in a time-dependent manner. It is well known that mechanosensitive...... the biomechanical environment of the mechanosensitive nerve endings, therefore, the structure as well as the tension, stress and strain distribution in the GI wall is important for the sensory and motor function. Biomechanical remodeling of diabetic GI tract including alterations of residual strain and increase...

  18. A new chromosome was born: comparative chromosome painting in Boechera.

    Science.gov (United States)

    Koch, Marcus A

    2015-09-01

    Comparative chromosome painting is a powerful tool to study the evolution of chromosomes and genomes. Analyzing karyotype evolution in cruciferous plants highlights the origin of aberrant chromosomes in apomictic Boechera and further establishes the cruciferous plants as important model system for our understanding of plant chromosome and genome evolution. PMID:26228436

  19. Matrix Remodeling Promotes Pulmonary Hypertension through Feedback Mechanoactivation of the YAP/TAZ-miR-130/301 Circuit

    Directory of Open Access Journals (Sweden)

    Thomas Bertero

    2015-11-01

    Full Text Available Pulmonary hypertension (PH is a deadly vascular disease with enigmatic molecular origins. We found that vascular extracellular matrix (ECM remodeling and stiffening are early and pervasive processes that promote PH. In multiple pulmonary vascular cell types, such ECM stiffening induced the microRNA-130/301 family via activation of the co-transcription factors YAP and TAZ. MicroRNA-130/301 controlled a PPARγ-APOE-LRP8 axis, promoting collagen deposition and LOX-dependent remodeling and further upregulating YAP/TAZ via a mechanoactive feedback loop. In turn, ECM remodeling controlled pulmonary vascular cell crosstalk via such mechanotransduction, modulation of secreted vasoactive effectors, and regulation of associated microRNA pathways. In vivo, pharmacologic inhibition of microRNA-130/301, APOE, or LOX activity ameliorated ECM remodeling and PH. Thus, ECM remodeling, as controlled by the YAP/TAZ-miR-130/301 feedback circuit, is an early PH trigger and offers combinatorial therapeutic targets for this devastating disease.

  20. ACE2 and vasoactive peptides: novel players in cardiovascular/renal remodeling and hypertension.

    Science.gov (United States)

    Mendoza-Torres, Evelyn; Oyarzún, Alejandra; Mondaca-Ruff, David; Azocar, Andrés; Castro, Pablo F; Jalil, Jorge E; Chiong, Mario; Lavandero, Sergio; Ocaranza, María Paz

    2015-08-01

    The renin-angiotensin system (RAS) is a key component of cardiovascular physiology and homeostasis due to its influence on the regulation of electrolyte balance, blood pressure, vascular tone and cardiovascular remodeling. Deregulation of this system contributes significantly to the pathophysiology of cardiovascular and renal diseases. Numerous studies have generated new perspectives about a noncanonical and protective RAS pathway that counteracts the proliferative and hypertensive effects of the classical angiotensin-converting enzyme (ACE)/angiotensin (Ang) II/angiotensin type 1 receptor (AT1R) axis. The key components of this pathway are ACE2 and its products, Ang-(1-7) and Ang-(1-9). These two vasoactive peptides act through the Mas receptor (MasR) and AT2R, respectively. The ACE2/Ang-(1-7)/MasR and ACE2/Ang-(1-9)/AT2R axes have opposite effects to those of the ACE/Ang II/AT1R axis, such as decreased proliferation and cardiovascular remodeling, increased production of nitric oxide and vasodilation. A novel peptide from the noncanonical pathway, alamandine, was recently identified in rats, mice and humans. This heptapeptide is generated by catalytic action of ACE2 on Ang A or through a decarboxylation reaction on Ang-(1-7). Alamandine produces the same effects as Ang-(1-7), such as vasodilation and prevention of fibrosis, by interacting with Mas-related GPCR, member D (MrgD). In this article, we review the key roles of ACE2 and the vasoactive peptides Ang-(1-7), Ang-(1-9) and alamandine as counter-regulators of the ACE-Ang II axis as well as the biological properties that allow them to regulate blood pressure and cardiovascular and renal remodeling. PMID:26275770

  1. Chimpanzee chromosome 13 is homologous to human chromosome 2p

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Similarities between human and chimpanzee chromosomes are shown by chromosome banding techniques and somatic cell hybridization techniques. Cell hybrids were obtained from the chimpanzee lymphocyte LE-7, and the Chinese hamster mutant cell, Gal-2. Experiments showed that the ACPL, MDHs, and Gal-Act genes could be assigned to chimpanzee chromosome 13, and since these genes have been assigned to human chromosme 2p, it is suggested that chimpanzee chromosome 13 is homologous to human chromosome 2p. (HLW)

  2. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs

  3. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  4. Chromosome numbers in Bromeliaceae

    OpenAIRE

    2000-01-01

    The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. u...

  5. Relocalization of human chromatin remodeling cofactor TIP48 in mitosis

    International Nuclear Information System (INIS)

    TIP48 is a highly conserved eukaryotic AAA+ protein which is an essential cofactor for several complexes involved in chromatin acetylation and remodeling, transcriptional and developmental regulation and nucleolar organization and trafficking. We show that TIP48 abundance in HeLa cells did not change during the cell cycle, nor did its distribution in various biochemical fractions. However, we observed distinct changes in the subcellular localization of TIP48 during M phase using immunofluorescence microscopy. Our studies demonstrate that in interphase cells TIP48 was found mainly in the nucleus and exhibited a distinct localization in the nuclear periphery. As the cells entered mitosis, TIP48 was excluded from the condensing chromosomes but showed association with the mitotic apparatus. During anaphase, some TIP48 was detected in the centrosome colocalizing with tubulin but the strongest staining appeared in the mitotic equator associated with the midzone central spindle. Accumulation of TIP48 in the midzone and the midbody was observed in late telophase and cytokinesis. This redeployment of TIP48 during anaphase and cytokinesis was independent of microtubule assembly. The relocation of endogenous TIP48 to the midzone/midbody under physiological conditions suggests a novel and distinct function for TIP48 in mitosis and possible involvement in the exit of mitosis

  6. Performance Requirements on Remodeling Apartment Housing and TOPSIS Evaluation

    OpenAIRE

    Jaeho Cho; Jaeyoul Chun

    2015-01-01

    Functional improvement needed in remodeling projects is determined by users in a complex manner since remodeling projects require performance improvement against deterioration. This study defines fundamental Remodeling Performance Criteria (RPC) for apartment housing by referring to performance criteria of both domestic and international performance-related systems. In this case study, performance evaluation of Construction Element Method (CEM) for remodeling projects was conducted based on R...

  7. New predictive model for monitoring bone remodeling

    Czech Academy of Sciences Publication Activity Database

    Bougherara, H.; Klika, Václav; Maršík, František; Mařík, I.; Yahia, L.H.

    95A, č. 1 (2010), s. 9-24. ISSN 1549-3296 R&D Projects: GA ČR GA106/03/1073; GA ČR(CZ) GA106/03/0958 Institutional research plan: CEZ:AV0Z20760514 Keywords : bone remodeling * open system thermodynamics * bone biochemistry Subject RIV: BJ - Thermodynamics Impact factor: 3.044, year: 2010

  8. Link between vitamin D and airway remodeling

    Directory of Open Access Journals (Sweden)

    Berraies A

    2014-04-01

    Full Text Available Anissa Berraies, Kamel Hamzaoui, Agnes HamzaouiPediatric Respiratory Diseases Department, Abderrahmen Mami Hospital, Ariana, and Research Unit 12SP15 Tunis El Manar University, Tunis, TunisiaAbstract: In the last decade, many epidemiologic studies have investigated the link between vitamin D deficiency and asthma. Most studies have shown that vitamin D deficiency increases the risk of asthma and allergies. Low levels of vitamin D have been associated with asthma severity and loss of control, together with recurrent exacerbations. Remodeling is an early event in asthma described as a consequence of production of mediators and growth factors by inflammatory and resident bronchial cells. Consequently, lung function is altered, with a decrease in forced expiratory volume in one second and exacerbated airway hyperresponsiveness. Subepithelial fibrosis and airway smooth muscle cell hypertrophy are typical features of structural changes in the airways. In animal models, vitamin D deficiency enhances inflammation and bronchial anomalies. In severe asthma of childhood, major remodeling is observed in patients with low vitamin D levels. Conversely, the antifibrotic and antiproliferative effects of vitamin D in smooth muscle cells have been described in several experiments. In this review, we briefly summarize the current knowledge regarding the relationship between vitamin D and asthma, and focus on its effect on airway remodeling and its potential therapeutic impact for asthma.Keywords: vitamin D, asthma, airway remodeling, airway smooth muscle, supplementation

  9. Interleukin-20 promotes airway remodeling in asthma.

    Science.gov (United States)

    Gong, Wenbin; Wang, Xin; Zhang, Yuguo; Hao, Junqing; Xing, Chunyan; Chu, Qi; Wang, Guicheng; Zhao, Jiping; Wang, Junfei; Dong, Qian; Liu, Tian; Zhang, Yuanyuan; Dong, Liang

    2014-12-01

    Previous studies have demonstrated that interleukin-20 (IL-20) is a pro-inflammatory cytokine, and it has been implicated in psoriasis, lupus nephritis, rheumatoid arthritis, atherosclerosis, and ulcerative colitis. Little is known about the effects of IL-20 in airway remodeling in asthma. The aim of our study was to demonstrate the function of IL-20 in airway remodeling in asthma. To identify the expression of IL-20 and its receptor, IL-20R1/IL-20R2, in the airway epithelium in bronchial tissues, bronchial biopsy specimens were collected from patients and mice with asthma and healthy subjects and stained with specific antibodies. To characterize the effects of IL-20 in asthmatic airway remodeling, we silenced and stimulated IL-20 in cell lines isolated from mice by shRNA and recombinant protein approaches, respectively, and detected the expression of α-SMA and FN-1 by Western blot analysis. First, overexpression of IL-20 and its receptor, IL-20R1/IL-20R2, was detected in the airway epithelium collected from patients and mice with asthma. Second, IL-20 increased the expression of fibronectin-1 and α-SMA, and silencing of IL-20 in mouse lung epithelial (MLE)-12 cells decreased the expression of fibronectin-1 and α-SMA. IL-20 may be a critical cytokine in airway remodeling in asthma. This study indicates that targeting IL-20 and/or its receptors may be a new therapeutic strategy for asthma. PMID:25028099

  10. Connexin Remodeling Contributes to Atrial Fibrillation

    OpenAIRE

    Michelle M Jennings; J Kevin Donahue

    2013-01-01

    Atrial fibrillation significantly contributes to mortality and morbidity through increased risk of stroke, heart failure and myocardial infarcts. Investigations of mechanisms responsible for the development and maintenance of atrial fibrillation have highlighted the importance of gap junctional remodeling. Connexins 40 and 43, the major atrial gap junctional proteins, undergo considerable alterations in expression and localization in atrial fibrillation, creating an environment conducive to s...

  11. Remodelling of flash furnace for coal firing

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Z.

    1982-05-01

    The Chichiku Cement Co. has succeeded in re-converting all its cement plants from oil to coal firing system with no impairment at all to production rate or to unit energy consumption. The reconversion wea achieved by remodelling four of its five principal kilns from a system of suspension preheater with calciner to the C-SF kiln system.

  12. MYOCARDIAL REMODELING IN ISCHEMIC HEART DISEASE

    Directory of Open Access Journals (Sweden)

    A. N. Zakirova

    2016-01-01

    Full Text Available Aim. To study the myocardial remodeling features in patients with stable angina depending on disease severity and experienced myocardial infarction (MI.Material and methods. 148 male patients with stable angina were examined and randomized into 3 groups (G1-G3. 52 patients of G1 had angina of I-II functional class (FC. 49 patients of G2 had angina of III FC, and 47 patients of G3 had angina of IV FC. History of MI had 79,5, 87.2 and 92.6% of patients in G1, G2 and G3 respectively. 35 healthy men were included into control group. Coronarography, bicycle ergometry and 24-hour ECG monitoring was performed. Left ventricular (LV function and remodeling was assessed with echocardiography.Results. G3 patients had LV eccentric hypertrophy as a result of postinfarction cardiosclerosis which accompanied with LV systolic dysfunction, a myocardial stress increasing and LV spherification. G1 patients had no any significant disorders of LV systolic function.Conclusion. Severe ischemic heart disease is associated with a dysadaptive remodeling unlike mild ischemic heart disease, which is associated with an adaptive myocardial remodeling.

  13. Re-Modelling as De-Professionalisation

    Science.gov (United States)

    Thompson, Meryl

    2006-01-01

    The article sets out the consequences of the British Government's remodelling agenda and its emphasis on less demarcation, for the professional status of teachers in England. It describes how the National Agreement on Raising Standards and Tackling Workload, reached between five of the six trade unions for teachers and headteachers paves the way…

  14. Micromechanics of human mitotic chromosomes

    International Nuclear Information System (INIS)

    Eukaryote cells dramatically reorganize their long chromosomal DNAs to facilitate their physical segregation during mitosis. The internal organization of folded mitotic chromosomes remains a basic mystery of cell biology; its understanding would likely shed light on how chromosomes are separated from one another as well as into chromosome structure between cell divisions. We report biophysical experiments on single mitotic chromosomes from human cells, where we combine micromanipulation, nano-Newton-scale force measurement and biochemical treatments to study chromosome connectivity and topology. Results are in accord with previous experiments on amphibian chromosomes and support the 'chromatin network' model of mitotic chromosome structure. Prospects for studies of chromosome-organizing proteins using siRNA expression knockdowns, as well as for differential studies of chromosomes with and without mutations associated with genetic diseases, are also discussed

  15. Vibrio chromosomes share common history

    Directory of Open Access Journals (Sweden)

    Gevers Dirk

    2010-05-01

    Full Text Available Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II were identified from 19 sequenced Vibrionales genomes and their phylogenetic comparison suggests consistent phylogenies for each chromosome. Additionally, study of the gene organization and phylogeny of the respective origins of replication confirmed the shared history. Conclusions Thus, while elements within the chromosomes may have experienced significant genetic mobility, the backbones share a common history. This allows conclusions based on multilocus sequence analysis (MLSA for one chromosome to be applied equally to both chromosomes.

  16. Chd1 remodelers maintain open chromatin and regulate the epigenetics of differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Jenna [Department of Biosciences and Nutrition, Center for Biosciences, Karolinska Institutet (Sweden); Ekwall, Karl, E-mail: karl.ekwall@ki.se [Department of Biosciences and Nutrition, Center for Biosciences, Karolinska Institutet (Sweden); School of Life Sciences, University College Sodertorn, NOVUM, Huddinge (Sweden)

    2010-05-01

    Eukaryotic DNA is packaged around octamers of histone proteins into nucleosomes, the basic unit of chromatin. In addition to enabling meters of DNA to fit within the confines of a nucleus, the structure of chromatin has functional implications for cell identity. Covalent chemical modifications to the DNA and to histones, histone variants, ATP-dependent chromatin remodelers, small noncoding RNAs and the level of chromatin compaction all contribute to chromosomal structure and to the activity or silencing of genes. These chromatin-level alterations are defined as epigenetic when they are heritable from mother to daughter cell. The great diversity of epigenomes that can arise from a single genome permits a single, totipotent cell to generate the hundreds of distinct cell types found in humans. Two recent studies in mouse and in fly have highlighted the importance of Chd1 chromatin remodelers for maintaining an open, active chromatin state. Based on evidence from fission yeast as a model system, we speculate that Chd1 remodelers are involved in the disassembly of nucleosomes at promoter regions, thus promoting active transcription and open chromatin. It is likely that these nucleosomes are specifically marked for disassembly by the histone variant H2A.Z.

  17. Changes in Nuclear Orientation Patterns of Chromosome 11 during Mouse Plasmacytoma Development

    Directory of Open Access Journals (Sweden)

    Ann-Kristin Schmälter

    2015-10-01

    Full Text Available Studying changes in nuclear architecture is a unique approach toward the understanding of nuclear remodeling during tumor development. One aspect of nuclear architecture is the orientation of chromosomes in the three-dimensional nuclear space. We studied mouse chromosome 11 in lymphocytes of [T38HxBALB/c]N mice with a reciprocal translocation between chromosome X and 11 (T38HT(X;11 exhibiting a long chromosome T(11;X and a short chromosome T(X;11 and in fast-onset plasmacytomas (PCTs induced in the same strain. We determined the three-dimensional orientation of chromosome 11 using a mouse chromosome 11 specific multicolor banding probe. We also examined the nuclear position of the small translocation chromosome T(X;11 which contains cytoband 11E2 and parts of E1. Chromosomes can point either with their centromeric or with their telomeric end toward the nuclear center or periphery, or their position is found in parallel to the nuclear border. In T38HT(X;11 nuclei, the most frequently observed orientation pattern was with both chromosomes 11 in parallel to the nuclear border (“PP”. PCT cells showed nuclei with two or more copies of chromosome 11. In PCTs, the most frequent orientation pattern was with one chromosome in parallel and the other pointing with its centromeric end toward the nuclear periphery (“CP”. There is a significant difference between the orientation patterns observed in T38HT(X;11 and in PCT nuclei (P < .0001.

  18. Shelterin Protects Chromosome Ends by Compacting Telomeric Chromatin.

    Science.gov (United States)

    Bandaria, Jigar N; Qin, Peiwu; Berk, Veysel; Chu, Steven; Yildiz, Ahmet

    2016-02-11

    Telomeres, repetitive DNA sequences at chromosome ends, are shielded against the DNA damage response (DDR) by the shelterin complex. To understand how shelterin protects telomere ends, we investigated the structural organization of telomeric chromatin in human cells using super-resolution microscopy. We found that telomeres form compact globular structures through a complex network of interactions between shelterin subunits and telomeric DNA, but not by DNA methylation, histone deacetylation, or histone trimethylation at telomeres and subtelomeric regions. Mutations that abrogate shelterin assembly or removal of individual subunits from telomeres cause up to a 10-fold increase in telomere volume. Decompacted telomeres accumulate DDR signals and become more accessible to telomere-associated proteins. Recompaction of telomeric chromatin using an orthogonal method displaces DDR signals from telomeres. These results reveal the chromatin remodeling activity of shelterin and demonstrate that shelterin-mediated compaction of telomeric chromatin provides robust protection of chromosome ends against the DDR machinery. PMID:26871633

  19. Atrial Electrical Remodeling and Sleep Disordered Breathing

    Directory of Open Access Journals (Sweden)

    Adrian Baranchuk; Diego Conde

    2013-08-01

    Full Text Available To the Editor: We read with interest the article from Bitter et al. (1 published in the last volume of JAFIB. This non-systematic review covers some of the most important physiopathological aspects of the link between sleep disordered breathing (SDB and atrial fibrillation (AFib. We do agree with the authors on the role of hypertension, endothelial dysfunction and inflammation. These topics were, to our understanding and perspective, very well covered by the authors on this review. However, despite that the authors mentioned atrial remodeling a couple of times during their review, we are not sure that this topic and specifically atrial electrical remodeling, was properly discussed and referenced. The pathophysiology linking SDB to AF is multifactorial and may involve repetitive hypoxemia, increased sympathetic drive, fluctuations in intrathoracic pressure and systemic inflammation (2. These physiologic changes may induce structural and electrical remodeling serving as a substrate to the development of AFib. An indirect marker for such electrical remodeling is the prolongation of atrial conduction time, represented by increased maximum P-wave duration in the surface ECG. In a prior study, we showed that an increased P-wave duration has been associated with SDB (3. Interatrial block (IAB, defined as a surface P-wave duration > 120 ms, was more prevalent in patients with moderate-severe SDB (34.7% SDB vs. 0% controls, p 25 were independent predictors of maximum P-wave duration (p=0.001 and p<0.001 respectively (3. Another non-invasive method to determine atrial electrical remodeling is the Signal-averaged P-wave (SAPW duration. The SAPW duration represents the average of all P-wave durations in a given number of consecutive heartbeats. We recently postulated that SAPW would be useful to identify atrial electrical remodeling in patients with severe SDB and that treatment with C-PAP for 4-6 weeks may induce reverse atrial electrical remodeling (4

  20. Three axis attitude control system

    Science.gov (United States)

    Studer, Philip A. (Inventor)

    1988-01-01

    A three-axis attitude control system for an orbiting body comprised of a motor driven flywheel supported by a torque producing active magnetic bearing is described. Free rotation of the flywheel is provided about its central axis and together with limited angular torsional deflections of the flywheel about two orthogonal axes which are perpendicular to the central axis. The motor comprises an electronically commutated DC motor, while the magnetic bearing comprises a radially servoed permanent magnet biased magnetic bearing capable of producing cross-axis torques on the flywheel. Three body attitude sensors for pitch, yaw and roll generate respective command signals along three mutually orthogonal axes (x, y, z) which are coupled to circuit means for energizing a set of control coils for producing torques about two of the axes (x and y) and speed control of the flywheel about the third (z) axis. An energy recovery system, which is operative during motor deceleration, is also included which permits the use of a high-speed motor to perform effectively as a reactive wheel suspended in the magnetic bearing.

  1. Simulated bone remodeling around tilted dental implants in the anterior maxilla.

    Science.gov (United States)

    Wang, Chao; Zhang, Weiping; Ajmera, Deepal Haresh; Zhang, Yun; Fan, Yubo; Ji, Ping

    2016-06-01

    Dental implants have to be placed with the long axis in different angulations due to the change in bone morphology. The objective of this study was to investigate the different bone remodeling response induced by the tilted dental implants and to assess whether it could lead to bone loss and implant failure. In this study, bone remodeling due to palato-labially inclined dental implants placed in the anterior maxillary incisor region was simulated. CT-based finite element models of a maxillary bone with dental implants were created herein. Five dental implants were placed at [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text], respectively. The remodeling progression was recorded and compared. Model [Formula: see text] (palatal side) shows the highest bone density values, but the inclined implant at [Formula: see text] (labial side) leads to significant bone loss. From a biomechanical perspective, it is speculated that a palatally inclined implant is more likely to enhance the bone density in the maxillary anterior region, but labial inclination of implant could jeopardize its stability. PMID:26285769

  2. Easy axis switching in magnetite

    International Nuclear Information System (INIS)

    The easy magnetic axis switching in magnetite is investigated. Magnetization data confirmed activation character of the process with activation energy of the same order as that of the Verwey transition, suggesting common origin. On the other hand this activation energy rises with pressure (up to 1.2GPa), unlike TV. The axis switching is clearly reflected in field dependence of resistivity and the direct structural data showed that it is simultaneous with the reorganization of structure. Thus, control of the structure can be possible with the application of magnetic field, as in shape memory materials. Finally, NMR showed that all, possibly decoupled entities: lattice distortion and charge and orbital orderings, change simultaneously while the axis switching occurs.

  3. Vertical axis wind turbine airfoil

    Science.gov (United States)

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

    2012-12-18

    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  4. Chromosome numbers in Bromeliaceae

    Directory of Open Access Journals (Sweden)

    Cotias-de-Oliveira Ana Lúcia Pires

    2000-01-01

    Full Text Available The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. utriculosa. The chromosome number of all species was determined for the first time, except for Billbergia chlorosticta and Cryptanthus bahianus. Our data supports the hypothesis of a basic number of x = 25 for the Bromeliaceae family and decreasing aneuploidy in the genus Cryptanthus.

  5. Those amazing dinoflagellate chromosomes

    Institute of Scientific and Technical Information of China (English)

    PETER J RIZZO

    2003-01-01

    Dinoflagellates are a very large and diverse group of eukaryotic algae that play a major role in aquatic food webs of both fresh water and marine habitats. Moreover, the toxic members of this group pose a health threat in the form of red tides. Finally, dinoflagellates are of great evolutionary importance,because of their taxonomic position, and their unusual chromosome structure and composition. While the cytoplasm of dinoflagellates is typically eukaryotic, the nucleus is unique when compared to the nucleus of other eukaryotes. More specifically, while the chromosomes of all other eukaryotes contain histones,dinoflagellate chromosomes lack histones completely. There are no known exceptions to this observation: all dinoflagellates lack histones, and all other eukaryotes contain histones. Nevertheless, dinoflagellates remain a relatively unstudied group of eukaryotes.

  6. Two-axis angular effector

    International Nuclear Information System (INIS)

    A new class of coplanar two-axis angular effectors is described. These effectors combine a two-axis rotational joint analogous to a Cardan joint with linear actuators in a manner to produce a wider range of rotational motion about both axes defined by the joint. This new class of effectors also allows design of robotic manipulators having very high strength and efficiency. These effectors are particularly suited for remote operation in unknown surroundings, because of their extraordinary versatility. An immediate application is to the problems which arise in nuclear waste remediation. 11 figs

  7. Helical axis stellarator equilibrium model

    International Nuclear Information System (INIS)

    An asymptotic model is developed to study MHD equilibria in toroidal systems with a helical magnetic axis. Using a characteristic coordinate system based on the vacuum field lines, the equilibrium problem is reduced to a two-dimensional generalized partial differential equation of the Grad-Shafranov type. A stellarator-expansion free-boundary equilibrium code is modified to solve the helical-axis equations. The expansion model is used to predict the equilibrium properties of Asperators NP-3 and NP-4. Numerically determined flux surfaces, magnetic well, transform, and shear are presented. The equilibria show a toroidal Shafranov shift

  8. Eosinophil-Mediated Cholinergic Nerve Remodeling

    OpenAIRE

    Durcan, Niamh; Costello, Richard W; McLean, W. Graham; Blusztajn, Jan; Madziar, Beata; Fenech, Anthony G; Hall, Ian P; Gleich, Gerard J.; McGarvey, Lorcan; Walsh, Marie-Therese

    2006-01-01

    Eosinophils are observed to localize to cholinergic nerves in a variety of inflammatory conditions such as asthma, rhinitis, eosinophilic gastroenteritis, and inflammatory bowel disease, where they are also responsible for the induction of cell signaling.Wehypothesized that a consequence of eosinophil localization to cholinergic nerves would involve a neural remodeling process. Eosinophil co-culture with cholinergic IMR32 cells led to increased expression of the M2 muscar...

  9. PHAGOCYTOSIS AND REMODELING OF COLLAGEN MATRICES

    OpenAIRE

    Abraham, Leah C.; Dice, J. Fred; Lee, Kyongbum; Kaplan, David L.

    2007-01-01

    The biodegradation of collagen and the deposition of new collagen-based extracellular matrices are of central importance in tissue remodeling and function. Similarly, for collagen-based biomaterials used in tissue engineering, the degradation of collagen scaffolds with accompanying cellular infiltration and generation of new extracellular matrix is critical for integration of in vitro grown tissues in vivo. In earlier studies we observed significant impact of collagen structure on primary lun...

  10. Cell wall remodeling under abiotic stress

    OpenAIRE

    Tenhaken, Raimund

    2015-01-01

    Plants exposed to abiotic stress respond to unfavorable conditions on multiple levels. One challenge under drought stress is to reduce shoot growth while maintaining root growth, a process requiring differential cell wall synthesis and remodeling. Key players in this process are the formation of reactive oxygen species (ROS) and peroxidases, which initially cross-link phenolic compounds and glycoproteins of the cell walls causing stiffening. The function of ROS shifts after having converted a...

  11. Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

    Directory of Open Access Journals (Sweden)

    Yerle Martine

    2003-11-01

    Full Text Available Abstract A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+ translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5 were elaborated and hybridised independently on chromosomal preparations of the bull who was a carrier of the mosaic translocation. The impossibility of differentiating chromosomes 2 and der(2 from other chromosomes of the metaphases did not allow the production of painting probes for these chromosomes. For all experiments, the quality of painting was comparable to that usually observed with probes obtained from flow-sorted chromosomes. The results obtained allowed confirmation of the interpretations proposed with G-banding karyotype analyses. In the bovine case, however, the reciprocity of the translocation could not be proven. The results presented in this paper show the usefulness of the microdissection technique for characterising chromosomal rearrangements in species for which commercial probes are not available. They also confirmed that the main limiting factor of the technique is the quality of the chromosomal preparations, which does not allow the identification of target chromosomes or chromosome fragments in all cases.

  12. Application of Petri Nets in Bone Remodeling

    Directory of Open Access Journals (Sweden)

    Lingxi Li

    2009-07-01

    Full Text Available Understanding a mechanism of bone remodeling is a challenging task for both life scientists and model builders, since this highly interactive and nonlinear process can seldom be grasped by simple intuition. A set of ordinary differential equations (ODEs have been built for simulating bone formation as well as bone resorption. Although solving ODEs numerically can provide useful predictions for dynamical behaviors in a continuous time frame, an actual bone remodeling process in living tissues is driven by discrete events of molecular and cellular interactions. Thus, an event-driven tool such as Petri nets (PNs, which may dynamically and graphically mimic individual molecular collisions or cellular interactions, seems to augment the existing ODE-based systems analysis. Here, we applied PNs to expand the ODE-based approach and examined discrete, dynamical behaviors of key regulatory molecules and bone cells. PNs have been used in many engineering areas, but their application to biological systems needs to be explored. Our PN model was based on 8 ODEs that described an osteoprotegerin linked molecular pathway consisting of 4 types of bone cells. The models allowed us to conduct both qualitative and quantitative evaluations and evaluate homeostatic equilibrium states. The results support that application of PN models assists understanding of an event-driven bone remodeling mechanism using PN-specific procedures such as places, transitions, and firings.

  13. Central airways remodeling in COPD patients

    Directory of Open Access Journals (Sweden)

    Pini L

    2014-09-01

    Full Text Available Laura Pini,1 Valentina Pinelli,2 Denise Modina,1 Michela Bezzi,3 Laura Tiberio,4 Claudio Tantucci1 1Unit of Respiratory Medicine, Department of Clinical and Experimental Sciences, University of Brescia, 2Department of Respiratory Medicine, Spedali Civili di Brescia, 3Department Bronchoscopy, Spedali Civili di Brescia, 4Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy Background: The contribution to airflow obstruction by the remodeling of the peripheral airways in chronic obstructive pulmonary disease (COPD patients has been well documented, but less is known about the role played by the large airways. Few studies have investigated the presence of histopathological changes due to remodeling in the large airways of COPD patients. Objectives: The aim of this study was to verify the presence of airway remodeling in the central airways of COPD patients, quantifying the airway smooth muscle (ASM area and the extracellular matrix (ECM protein deposition, both in the subepithelial region and in the ASM, and to verify the possible contribution to airflow obstruction by the above mentioned histopathological changes. Methods: Biopsies of segmental bronchi spurs were performed in COPD patients and control smoker subjects and immunostained for collagen type I, versican, decorin, biglycan, and alpha-smooth muscle actin. ECM protein deposition was measured at both subepithelial, and ASM layers. Results: The staining for collagen I and versican was greater in the subepithelial layer of COPD patients than in control subjects. An inverse correlation was found between collagen I in the subepithelial layer and both forced expiratory volume in 1 second and ratio between forced expiratory volume in 1 second and forced vital capacity. A statistically significant increase of the ASM area was observed in the central airways of COPD patients versus controls. Conclusion: These findings indicate that airway remodeling also affects

  14. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B; Vogel, F; Noer, H; Mikkelsen, M

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation with...

  15. The Y Chromosome

    Science.gov (United States)

    Offner, Susan

    2010-01-01

    The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

  16. Chromosomes, cancer and radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Samouhos, E.

    1983-08-01

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available.

  17. Chromosomes, cancer and radiosensitivity

    International Nuclear Information System (INIS)

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available

  18. Chromosome Morphology in Kniphofia.

    Directory of Open Access Journals (Sweden)

    J. M. J de Wet

    1960-12-01

    Full Text Available A number of species and varieties of the genus  Kniphofia (Liliaceae were studied cytologically. The somatic chromosome number is  2n = 12 in all the species. This is also true in  Notosceptrum natalense Baker.

  19. Telomere dysfunction and chromosome instability

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, John P., E-mail: jmurnane@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, 2340 Sutter Street, San Francisco, CA 94143-1331 (United States)

    2012-02-01

    The ends of chromosomes are composed of a short repeat sequence and associated proteins that together form a cap, called a telomere, that keeps the ends from appearing as double-strand breaks (DSBs) and prevents chromosome fusion. The loss of telomeric repeat sequences or deficiencies in telomeric proteins can result in chromosome fusion and lead to chromosome instability. The similarity between chromosome rearrangements resulting from telomere loss and those found in cancer cells implicates telomere loss as an important mechanism for the chromosome instability contributing to human cancer. Telomere loss in cancer cells can occur through gradual shortening due to insufficient telomerase, the protein that maintains telomeres. However, cancer cells often have a high rate of spontaneous telomere loss despite the expression of telomerase, which has been proposed to result from a combination of oncogene-mediated replication stress and a deficiency in DSB repair in telomeric regions. Chromosome fusion in mammalian cells primarily involves nonhomologous end joining (NHEJ), which is the major form of DSB repair. Chromosome fusion initiates chromosome instability involving breakage-fusion-bridge (B/F/B) cycles, in which dicentric chromosomes form bridges and break as the cell attempts to divide, repeating the process in subsequent cell cycles. Fusion between sister chromatids results in large inverted repeats on the end of the chromosome, which amplify further following additional B/F/B cycles. B/F/B cycles continue until the chromosome acquires a new telomere, most often by translocation of the end of another chromosome. The instability is not confined to a chromosome that loses its telomere, because the instability is transferred to the chromosome donating a translocation. Moreover, the amplified regions are unstable and form extrachromosomal DNA that can reintegrate at new locations. Knowledge concerning the factors promoting telomere loss and its consequences is

  20. Organization of the bacterial chromosome.

    OpenAIRE

    Krawiec, S.; Riley, M

    1990-01-01

    Recent progress in studies on the bacterial chromosome is summarized. Although the greatest amount of information comes from studies on Escherichia coli, reports on studies of many other bacteria are also included. A compilation of the sizes of chromosomal DNAs as determined by pulsed-field electrophoresis is given, as well as a discussion of factors that affect gene dosage, including redundancy of chromosomes on the one hand and inactivation of chromosomes on the other hand. The distinction ...

  1. [Chromosomal organization of the genomes of small-chromosome plants].

    Science.gov (United States)

    Muravenko, O V; Zelenin, A V

    2009-11-01

    An effective approach to study the chromosome organization in genomes of plants with small chromosomes and/or with low-informative C-banding patterns was developed in the course of investigation of the karyotypes of cotton plant, camomile, flax, and pea. To increase the resolving power of chromosome analysis, methods were worked out for revealing early replication patterns on chromosomes and for artificial impairment of mitotic chromosome condensation with the use of a DNA intercalator, 9-aminoacridine (9-AMA). To estimate polymorphism of the patterns of C-banding of small chromosomes on preparations obtained with the use of 9-AMA, it is necessary to choose a length interval that must not exceed three average sizes of metaphase chromosomes without the intercalator. The use of 9-AMA increases the resolution of differential C- and OR-banding and the precision of physical chromosome mapping by the FISH method. Of particular importance in studying small chromosomes is optimization of the computer-aided methods used to obtain and process chromosome images. The complex approach developed for analysis of the chromosome organization in plant genomes was used to study the karyotypes of 24 species of the genus Linum L. It permitted their chromosomes to be identified for the first time, and, in addition, B chromosomes were discovered and studied in the karyotypes of the species of the section Syllinum. By similarity of the karyotypes, the studied flax species were distributed in eight groups in agreement with the clusterization of these species according to the results of RAPD analysis performed in parallel. Systematic positions and phylogenetic relationships of the studied flax species were verified. Out results can serve as an important argument in favour of the proposal to develop a special program for sequencing the genome of cultivated flax (L. usitatissimum L.), which is a major representative of small-chromosome species. PMID:20058798

  2. Vertical axis wind turbine acoustics

    OpenAIRE

    Pearson, Charlie

    2014-01-01

    Increasing awareness of the issues of climate change and sustainable energy use has led to growing levels of interest in small-scale, decentralised power generation. Small-scale wind power has seen significant growth in the last ten years, partly due to the political support for renewable energy and the introduction of Feed In Tariffs, which pay home owners for generating their own electricity. Due to their ability to respond quickly to changing wind conditions, small-scale vertical axis...

  3. Hypothalamus-Pituitary-Thyroid Axis.

    Science.gov (United States)

    Ortiga-Carvalho, Tania M; Chiamolera, Maria I; Pazos-Moura, Carmen C; Wondisford, Fredic E

    2016-01-01

    The hypothalamus-pituitary-thyroid (HPT) axis determines the set point of thyroid hormone (TH) production. Hypothalamic thyrotropin-releasing hormone (TRH) stimulates the synthesis and secretion of pituitary thyrotropin (thyroid-stimulating hormone, TSH), which acts at the thyroid to stimulate all steps of TH biosynthesis and secretion. The THs thyroxine (T4) and triiodothyronine (T3) control the secretion of TRH and TSH by negative feedback to maintain physiological levels of the main hormones of the HPT axis. Reduction of circulating TH levels due to primary thyroid failure results in increased TRH and TSH production, whereas the opposite occurs when circulating THs are in excess. Other neural, humoral, and local factors modulate the HPT axis and, in specific situations, determine alterations in the physiological function of the axis. The roles of THs are vital to nervous system development, linear growth, energetic metabolism, and thermogenesis. THs also regulate the hepatic metabolism of nutrients, fluid balance and the cardiovascular system. In cells, TH actions are mediated mainly by nuclear TH receptors (210), which modify gene expression. T3 is the preferred ligand of THR, whereas T4, the serum concentration of which is 100-fold higher than that of T3, undergoes extra-thyroidal conversion to T3. This conversion is catalyzed by 5'-deiodinases (D1 and D2), which are TH-activating enzymes. T4 can also be inactivated by conversion to reverse T3, which has very low affinity for THR, by 5-deiodinase (D3). The regulation of deiodinases, particularly D2, and TH transporters at the cell membrane control T3 availability, which is fundamental for TH action. © 2016 American Physiological Society. Compr Physiol 6:1387-1428, 2016. PMID:27347897

  4. Role of arginase in vessel wall remodeling

    Directory of Open Access Journals (Sweden)

    William eDurante

    2013-05-01

    Full Text Available Arginase metabolizes the semi-essential amino acid L-arginine to L-ornithine and urea. There are two distinct isoforms of arginase, arginase I and II, which are encoded by separate genes and display differences in tissue distribution, subcellular localization, and molecular regulation. Blood vessels express both arginase I and II but their distribution appears to be cell-, vessel-, and species-specific. Both isoforms of arginase are induced by numerous pathologic stimuli and contribute to vascular cell dysfunction and vessel wall remodeling in several diseases. Clinical and experimental studies have documented increases in the expression and/or activity of arginase I or II in blood vessels following arterial injury and in pulmonary and arterial hypertension, aging, and atherosclerosis. Significantly, pharmacological inhibition or genetic ablation of arginase in animals ameliorates abnormalities in vascular cells and normalizes blood vessel architecture and function in all of these pathological states. The detrimental effect of arginase in vascular remodeling is attributable to its ability to stimulate vascular smooth muscle cell and endothelial cell proliferation, and collagen deposition by promoting the synthesis of polyamines and L-proline, respectively. In addition, arginase adversely impacts arterial remodeling by directing macrophages towards an inflammatory phenotype. Moreover, the proliferative, fibrotic, and inflammatory actions of arginase in the vasculature are further amplified by its capacity to inhibit nitric oxide synthesis by competing with nitric oxide synthase for substrate, L-arginine. Pharmacologic or molecular approaches targeting specific isoforms of arginase represent a promising strategy in treating obstructive fibroproliferative vascular disease.

  5. MYOCARDIAL REMODELING IN ISCHEMIC HEART DISEASE

    OpenAIRE

    A.N. Zakirova; R.G. Oganov; N.E. Zakirova; G. R. Klochkova; F.S. Musina

    2016-01-01

    Aim. To study the myocardial remodeling features in patients with stable angina depending on disease severity and experienced myocardial infarction (MI).Material and methods. 148 male patients with stable angina were examined and randomized into 3 groups (G1-G3). 52 patients of G1 had angina of I-II functional class (FC). 49 patients of G2 had angina of III FC, and 47 patients of G3 had angina of IV FC. History of MI had 79,5, 87.2 and 92.6% of patients in G1, G2 and G3 respectively. 35 healt...

  6. Chromosome 19 International Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ., Durham, NC (United States). Medical Center); Ropers, H.H. (Univ. Hospital Nijmegen, (The Netherlands). Dept. of Human Genetics); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1993-01-04

    The Second International Workshop on Human Chromosome 19 was hosted on January 25 and 26, 1992, by the Department of Human Genetics, University Hospital Nijmegen, The Netherlands, at the 'Meerdal Conference Center'. The workshop was supported by a grant from the European Community obtained through HUGO, the Dutch Research Organization (NWO) and the Muscular Dystrophy Association (MDA). Travel support for American participants was provided by the Department of Energy. The goals of this workshop were to produce genetic, physical and integrated maps of chromosome 19, to identify inconsistencies and gaps, and to discuss and exchange resources and techniques available for the completion of these maps. The second day of the meeting was largely devoted to region or disease specific efforts. In particular, the meeting served as a platform for assessing and discussing the recent progress made into the molecular elucidation of myotonic dystrophy.

  7. PARP inhibition and postinfarction myocardial remodeling.

    Science.gov (United States)

    Halmosi, Robert; Deres, Laszlo; Gal, Roland; Eros, Krisztian; Sumegi, Balazs; Toth, Kalman

    2016-08-01

    Coronary artery disease accounts for the greatest proportion of cardiovascular diseases therefore it is the major cause of death worldwide. Its therapeutic importance is indicated by still high mortality of myocardial infarction, which is one of the most severe forms of CVDs. Moreover, the risk of developing heart failure is very high among survivors. Heart failure is accompanied by high morbidity and mortality rate, therefore this topic is in the focus of researchers' interest. After a myocardial infarct, at first ventricular hypertrophy develops as a compensatory mechanism to decrease wall stress but finally leads to left ventricular dilation. This phenomenon is termed as myocardial remodeling. The main characteristics of underlying mechanisms involve cardiomyocyte growth, vessel changes and increased collagen production, in all of which several mechanical stress induced neurohumoral agents, oxidative stress and signal transduction pathways are involved. The long term activation of these processes ultimately leads to left ventricular dilation and heart failure with decreased systolic function. Oxidative stress causes DNA breaks producing the activation of nuclear poly(ADP-ribose) polymerase-1 (PARP-1) enzyme that leads to energy depletion and unfavorable modulation of different kinase cascades (Akt-1/GSK-3β, MAPKs, various PKC isoforms) and thus it promotes the development of heart failure. Therefore inhibition of PARP enzyme could offer a promising new therapeutical approach to prevent the onset of heart failure among postinfarction patients. The purpose of this review is to give a comprehensive summary about the most significant experimental results and mechanisms in postinfarction remodeling. PMID:27392900

  8. Abnormal bone remodelling in inflammatory arthritis

    Science.gov (United States)

    Bogoch, Earl R.; Moran, Erica

    1998-01-01

    Osteopenia is responsible for substantial comorbidity in patients suffering from rheumatoid arthritis and is an important factor in the surgical management of joint disease. In animal models of bone loss stimulated by inflammatory arthritis, increased bone remodelling and altered microstructure of bone have been documented. The subchondral bone plate near the joint surface is narrow and perforated by vascular inflammatory invasion, and in the shaft the thin cortices are weakened by giant resorption defects. Biomechanical tests and a mathematical model of bone strength suggest that cortical defects, much larger than those found in normal osteonal remodelling, are principally responsible for the experimentally observed loss of strength. Similarly, these defects may explain the increased femoral fracture risk in rheumatoid arthritis. The osteoclast, the cell resorbing bone, is demonstrated in increased number and activity in rheumatoid arthritis and in animal models. Bisphosphonates, drugs that inhibit osteoclast function, have been shown experimentally to reduce both focal and generalized osteopenia and to prevent loss of bone strength. Bisphosphonates also protect articular cartilage from damage characteristic of inflammatory arthritis. The mechanism of chondroprotection may be prevention of subchondral bone resorption by the osteoclast and also an altered distribution of bone marrow cells. Thus, bisphosphonates, currently in clinical use for other bone metabolic diseases, appear to have potential as prophylaxis and treatment for osteopenia and joint damage in inflammatory arthritis. PMID:9711159

  9. Histamine in regulation of bone remodeling processes

    Directory of Open Access Journals (Sweden)

    Marek Wiercigroch

    2013-08-01

    Full Text Available Bone remodeling is under autocrine, paracrine, endocrine and central nervous system control. One of the potential endogenous factors affecting bone remodeling is histamine, an endogenous amine which acts as a mediator of allergic reactions and neuromediator, and induces production of gastric acid. Histamine H1 receptor antagonists are widely used in the treatment of allergic conditions, H2 receptor antagonists in peptic ulcer disease, and betahistine (an H3 receptor antagonist and H1 receptor agonist is used in the treatment of Ménière’s disease.Excess histamine release in mastocytosis and allergic diseases may lead to development of osteoporosis. Clinical and population-based studies on the effects of histamine receptor antagonists on the skeletal system have not delivered unequivocal results.Expression of mRNA of histamine receptors has been discovered in bone cells (osteoblasts and osteoclasts. Histamine synthesis has been demonstrated in osteoclast precursors. Histamine increases bone resorption both by direct effects on osteoclast precursors and osteoclasts, and indirectly, by increasing the expression of RANKL in osteoblasts. In in vivo studies, H1 and H2 receptor antagonists exerted protective effects on the bone tissue, although not in all experimental models. In the present article, in vitro and in vivo studies conducted so far, concerning the effects of histamine and drugs modifying its activity on the skeletal system, have been reviewed.

  10. [Histamine in regulation of bone remodeling processes].

    Science.gov (United States)

    Wiercigroch, Marek; Folwarczna, Joanna

    2013-01-01

    Bone remodeling is under autocrine, paracrine, endocrine and central nervous system control. One of the potential endogenous factors affecting bone remodeling is histamine, an endogenous amine which acts as a mediator of allergic reactions and neuromediator, and induces production of gastric acid. Histamine H₁ receptor antagonists are widely used in the treatment of allergic conditions, H₂ receptor antagonists in peptic ulcer disease, and betahistine (an H₃ receptor antagonist and H₁ receptor agonist) is used in the treatment of Ménière's disease. Excess histamine release in mastocytosis and allergic diseases may lead to development of osteoporosis. Clinical and population-based studies on the effects of histamine receptor antagonists on the skeletal system have not delivered unequivocal results. Expression of mRNA of histamine receptors has been discovered in bone cells (osteoblasts and osteoclasts). Histamine synthesis has been demonstrated in osteoclast precursors. Histamine increases bone resorption both by direct effects on osteoclast precursors and osteoclasts, and indirectly, by increasing the expression of RANKL in osteoblasts. In in vivo studies, H₁ and H₂ receptor antagonists exerted protective effects on the bone tissue, although not in all experimental models. In the present article, in vitro and in vivo studies conducted so far, concerning the effects of histamine and drugs modifying its activity on the skeletal system, have been reviewed. PMID:24018454

  11. Epithelial Cell Apoptosis and Lung Remodeling

    Institute of Scientific and Technical Information of China (English)

    Kazuyoshi Kuwano

    2007-01-01

    Lung epithelium is the primary site of lung damage in various lung diseases. Epithelial cell apoptosis has been considered to be initial event in various lung diseases. Apoptosis signaling is classically composed of two principle pathways. One is a direct pathway from death receptor ligation to caspase cascade activation and cell death. The other pathway triggered by stresses such as drugs, radiation, infectious agents and reactive oxygen species is mediated by mitochondria. Endoplasmic reticulum has also been shown to be the organelle to mediate apoptosis.Epithelial cell death is followed by remodeling processes, which consist of epithelial and fibroblast activation,cytokine production, activation of coagulation pathway, neoangiogenesis, re-epithelialization and fibrosis.Epithelial and mesenchymal interaction plays important roles in these processes. Further understanding of apoptosis signaling and its regulation by novel strategies may lead to effective treatments against various lung diseases. We review the recent advances in the understanding of apoptosis signaling and discuss the involvement of apoptosis in lung remodeling.

  12. Atrial remodeling, fibrosis, and atrial fibrillation.

    Science.gov (United States)

    Jalife, José; Kaur, Kuljeet

    2015-08-01

    The fundamental mechanisms governing the perpetuation of atrial fibrillation (AF), the most common arrhythmia seen in clinical practice, are poorly understood, which explains in part why AF prevention and treatment remain suboptimal. Although some clinical parameters have been identified as predicting a transition from paroxysmal to persistent AF in some patients, the molecular, electrophysiological, and inflammation changes leading to such a progression have not been described in detail. Oxidative stress, atrial dilatation, calcium overload, inflammation, microRNAs, and myofibroblast activation are all thought to be involved in AF-induced atrial remodeling. However, it is unknown to what extent and at which time points such alterations influence the remodeling process that perpetuates AF. Here we postulate a working model that might open new pathways for future investigation into mechanisms of AF perpetuation. We start from the premise that the progression to AF perpetuation is the result of interplay among manifold signaling pathways with differing kinetics. Some such pathways have relatively fast kinetics (e.g., oxidative stress-mediated shortening of refractory period); others likely depend on molecular processes with slower kinetics (e.g., transcriptional changes in myocyte ion channel protein expression mediated through inflammation and fibroblast activation). We stress the need to fully understand the relationships among such pathways should one hope to identify novel, truly effective targets for AF therapy and prevention. PMID:25661032

  13. Glioblastoma adaptation traced through decline of an IDH1 clonal driver and macro-evolution of a double-minute chromosome

    DEFF Research Database (Denmark)

    Favero, Francesco; McGranahan, Nicholas; Salm, Maximilian P.;

    2015-01-01

    chromosome also incorporating miR26a-2. The WGS analysis uncovered progressive evolution of the double minute chromosome converging on the KIT/PDGFRA/PI3K/mTOR axis, superseding the IDH1 mutation in dominance in a mutually exclusive manner at recurrence, consequently the patient was treated with imatinib...

  14. Straining mode-dependent collagen remodeling in engineered cardiovascular tissue

    NARCIS (Netherlands)

    Rubbens, M.P.; Mol, A.; Marion, M.H. van; Hanemaaijer, R.; Bank, R.A.; Baaijens, F.P.T.; Bouten, C.V.C.

    2009-01-01

    Similar to native cardiovascular tissues, the mechanical properties of engineered cardiovascular constructs depend on the composition and quality of the extracellular matrix, which is a net result of matrix remodeling processes within the tissue. To improve tissue remodeling, and hence tissue mechan

  15. Molecular fundamentals of chromosomal mutagenesis

    International Nuclear Information System (INIS)

    Precise quantitative correlation between the yield of chromosome structure damages and the yield of DNA damages is shown when comparing data on molecular and cytogenetic investigations carried out in cultural Mammalia cells. As the chromosome structure damage is to be connected with the damage of its carcass structure, then it is natural that DNA damage in loop regions is not to affect considerably the structure, while DNA damage lying on the loop base and connected with the chromosome carcass is to play a determining role in chromosomal mutagenesis. This DNA constitutes 1-2% from the total quantity of nuclear DNA. If one accepts that damages of these regions of DNA are ''hot'' points of chromosomal mutagenesis, then it becomes clear why 1-2% of preparation damages in a cell are realized in chromosome structural damages

  16. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli;

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...... impedance spectroscopy was selected as the sensing method on a microfabricated chip with array of 12 electrode sets. Two independent chips (Chip1 and Chip2) were used for targeting the chromosomal fragments involved in the translocation. Each chip was differentially functionalized with DNA probes matching...

  17. Intraspecific chromosome variability

    Directory of Open Access Journals (Sweden)

    N Dubinin

    2010-12-01

    Full Text Available (Editorial preface. The publication is presented in order to remind us of one of dramatic pages of the history of genetics. It re-opens for the contemporary reader a comprehensive work marking the priority change from plant cytogenetics to animal cytogenetics led by wide population studies which were conducted on Drosophila polytene chromosomes. The year of the publication (1937 became the point of irretrievable branching between the directions of Old World and New World genetics connected with the problems of chromosome variability and its significance for the evolution of the species. The famous book of T. Dobzhansky (1937 was published by Columbia University in the US under the title “Genetics and the origin of species”, and in the shadow of this American ‘skybuilding’ all other works grew dim. It is remarkable that both Dobzhansky and Dubinin come to similar conclusions about the role of chromosomes in speciation. This is not surprising given that they both might be considered as representatives of the Russian genetic school, by their birth and education. Interestingly, Dobzhansky had never referred to the full paper of Dubinin et al. (1937, though a previous short communication in Nature (1936 was included together with all former papers on the related subject. In full, the volume of the original publication printed in the Biological Journal in Moscow comprised 47 pages, in that number 41 pages of the Russian text accompanied by 16 Figs, a table and reference list, and, above all, 6 pages of the English summary. This final part in English is now reproduced in the authors’ version with the only addition being the reference list in the originally printed form.

  18. Reference-assisted chromosome assembly

    OpenAIRE

    Kim, Jaebum; Larkin, Denis M; Cai, Qingle; Asan,; Zhang, Yongfen; Ge, Ri-Li; Auvil, Loretta; Capitanu, Boris; Zhang, Guojie; Lewin, Harris A.; Ma, Jian

    2013-01-01

    One of the most difficult problems in modern genomics is the assembly of full-length chromosomes using next generation sequencing (NGS) data. To address this problem, we developed “reference-assisted chromosome assembly” (RACA), an algorithm to reliably order and orient sequence scaffolds generated by NGS and assemblers into longer chromosomal fragments using comparative genome information and paired-end reads. Evaluation of results using simulated and real genome assemblies indicates that ou...

  19. Cyc17, a meiosis-specific cyclin, is essential for anaphase initiation and chromosome segregation in Tetrahymena thermophila.

    Science.gov (United States)

    Yan, Guan-Xiong; Dang, Huai; Tian, Miao; Zhang, Jing; Shodhan, Anura; Ning, Ying-Zhi; Xiong, Jie; Miao, Wei

    2016-07-17

    Although the role of cyclins in controlling nuclear division is well established, their function in ciliate meiosis remains unknown. In ciliates, the cyclin family has undergone massive expansion which suggests that diverse cell cycle systems exist, and this warrants further investigation. A screen for cyclins in the model ciliate Tetrahymena thermophila showed that there are 34 cyclins in this organism. Only 1 cyclin, Cyc17, contains the complete cyclin core and is specifically expressed during meiosis. Deletion of CYC17 led to meiotic arrest at the diakinesis-like metaphase I stage. Expression of genes involved in DNA metabolism and chromosome organization (chromatin remodeling and basic chromosomal structure) was repressed in cyc17 knockout matings. Further investigation suggested that Cyc17 is involved in regulating spindle pole attachment, and is thus essential for chromosome segregation at meiosis. These findings suggest a simple model in which chromosome segregation is influenced by Cyc17. PMID:27192402

  20. An Asymmetric Chromosome Pair Undergoes Synaptic Adjustment and Crossover Redistribution During Caenorhabditis elegans Meiosis: Implications for Sex Chromosome Evolution

    Science.gov (United States)

    Henzel, Jonathan V.; Nabeshima, Kentaro; Schvarzstein, Mara; Turner, B. Elizabeth; Villeneuve, Anne M.; Hillers, Kenneth J.

    2011-01-01

    Heteromorphic sex chromosomes, such as the X/Y pair in mammals, differ in size and DNA sequence yet function as homologs during meiosis; this bivalent asymmetry presents special challenges for meiotic completion. In Caenorhabditis elegans males carrying mnT12, an X;IV fusion chromosome, mnT12 and IV form an asymmetric bivalent: chromosome IV sequences are capable of pairing and synapsis, while the contiguous X portion of mnT12 lacks a homologous pairing partner. Here, we investigate the meiotic behavior of this asymmetric neo-X/Y chromosome pair in C. elegans. Through immunolocalization of the axis component HIM-3, we demonstrate that the unpaired X axis has a distinct, coiled morphology while synapsed axes are linear and extended. By showing that loci at the fusion-proximal end of IV become unpaired while remaining synapsed as pachytene progresses, we directly demonstrate the occurrence of synaptic adjustment in this organism. We further demonstrate that meiotic crossover distribution is markedly altered in males with the asymmetric mnT12/+ bivalent relative to controls, resulting in greatly reduced crossover formation near the X;IV fusion point and elevated crossovers at the distal end of the bivalent. In effect, the distal end of the bivalent acts as a neo-pseudoautosomal region in these males. We discuss implications of these findings for mechanisms that ensure crossover formation during meiosis. Furthermore, we propose that redistribution of crossovers triggered by bivalent asymmetry may be an important driving force in sex chromosome evolution. PMID:21212235

  1. Multiscale Bone Remodelling with Spatial P Systems

    CERN Document Server

    Cacciagrano, Diletta; Merelli, Emanuela; Tesei, Luca; 10.4204/EPTCS.40.6

    2010-01-01

    Many biological phenomena are inherently multiscale, i.e. they are characterized by interactions involving different spatial and temporal scales simultaneously. Though several approaches have been proposed to provide "multilayer" models, only Complex Automata, derived from Cellular Automata, naturally embed spatial information and realize multiscaling with well-established inter-scale integration schemas. Spatial P systems, a variant of P systems in which a more geometric concept of space has been added, have several characteristics in common with Cellular Automata. We propose such a formalism as a basis to rephrase the Complex Automata multiscaling approach and, in this perspective, provide a 2-scale Spatial P system describing bone remodelling. The proposed model not only results to be highly faithful and expressive in a multiscale scenario, but also highlights the need of a deep and formal expressiveness study involving Complex Automata, Spatial P systems and other promising multiscale approaches, such as ...

  2. Matrix Remodeling in Pulmonary Fibrosis and Emphysema.

    Science.gov (United States)

    Kulkarni, Tejaswini; O'Reilly, Philip; Antony, Veena B; Gaggar, Amit; Thannickal, Victor J

    2016-06-01

    Pulmonary fibrosis and emphysema are chronic lung diseases characterized by a progressive decline in lung function, resulting in significant morbidity and mortality. A hallmark of these diseases is recurrent or persistent alveolar epithelial injury, typically caused by common environmental exposures such as cigarette smoke. We propose that critical determinants of the outcome of the injury-repair processes that result in fibrosis versus emphysema are mesenchymal cell fate and associated extracellular matrix dynamics. In this review, we explore the concept that regulation of mesenchymal cells under the influence of soluble factors, in particular transforming growth factor-β1, and the extracellular matrix determine the divergent tissue remodeling responses seen in pulmonary fibrosis and emphysema. PMID:26741177

  3. Renovascular hypertension causes cerebral vascular remodeling

    Institute of Scientific and Technical Information of China (English)

    Yamei Tang; Xiangpen Li; Yi Li; Qingyu Shen; Xiaoming Rong; Ruxun Huang; Ying Peng

    2011-01-01

    Renovascular hypertensive rats (RHRs) were developed using the 2-kidney, 2-clip method. All RHRs at 10 weeks displayed high permeability of the cerebral surface blood vessels. Vascular casts of the RHRs showed that the vascular network was sparse. The arterioles of the RHRs at 10 weeks had smaller lumen diameters, but thicker vessel walls with hyalinosis formation compared with control animals. The endothelial cell membrane appeared damaged, and microthrombus formed. After ischemia, the infarction size was larger in RHRs than in control animals. These results suggest that cerebral arterioles in RHRs underwent structural remodeling. High blood pressure may aggravate the severity of brain injury in cerebral ischemia and affect the recovery of ischemia.

  4. PNPLA3 mediates hepatocyte triacylglycerol remodeling.

    Science.gov (United States)

    Ruhanen, Hanna; Perttilä, Julia; Hölttä-Vuori, Maarit; Zhou, You; Yki-Järvinen, Hannele; Ikonen, Elina; Käkelä, Reijo; Olkkonen, Vesa M

    2014-04-01

    The I148M substitution in patatin-like phospholipase domain containing 3 (PNPLA3(I148M)) determines a genetic form of nonalcoholic fatty liver disease. To elucidate the mode of PNPLA3 action in human hepatocytes, we studied effects of WT PNPLA3 (PNPLA3(WT)) and PNPLA3(I148M) on HuH7 cell lipidome after [(13)C]glycerol labeling, cellular turnover of oleic acid labeled with 17 deuterium atoms ([D17]oleic acid) in triacylglycerols (TAGs), and subcellular distribution of the protein variants. PNPLA3(I148M) induced a net accumulation of unlabeled TAGs, but not newly synthesized total [(13)C]TAGs. Principal component analysis (PCA) revealed that both PNPLA3(WT) and PNPLA3(I148M) induced a relative enrichment of TAGs with saturated FAs or MUFAs, with concurrent enrichment of polyunsaturated phosphatidylcholines. PNPLA3(WT) associated in PCA with newly synthesized [(13)C]TAGs, particularly 52:1 and 50:1, while PNPLA3(I148M) associated with similar preexisting TAGs. PNPLA3(WT) overexpression resulted in increased [D17]oleic acid labeling of TAGs during 24 h, and after longer incubations their turnover was accelerated, effects not detected with PNPLA3(I148M). PNPLA3(I148M) localized more extensively to lipid droplets (LDs) than PNPLA3(WT), suggesting that the substitution alters distribution of PNPLA3 between LDs and endoplasmic reticulum/cytosol. This study reveals a function of PNPLA3 in FA-selective TAG remodeling, resulting in increased TAG saturation. A defect in TAG remodeling activity likely contributes to the TAG accumulation observed in cells expressing PNPLA3(I148M). PMID:24511104

  5. Chromosome Connections: Compelling Clues to Common Ancestry

    Science.gov (United States)

    Flammer, Larry

    2013-01-01

    Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

  6. X-chromosome workshop.

    Science.gov (United States)

    Paterson, A D

    1998-01-01

    Researchers presented results of ongoing research to the X-chromosome workshop of the Fifth World Congress on Psychiatric Genetics, covering a wide range of disorders: X-linked infantile spasms; a complex phenotype associated with deletions of Xp11; male homosexuality; degree of handedness; bipolar affective disorder; schizophrenia; childhood onset psychosis; and autism. This report summarizes the presentations, as well as reviewing previous studies. The focus of this report is on linkage findings for schizophrenia and bipolar disorder from a number of groups. For schizophrenia, low positive lod scores were obtained for markers DXS991 and DXS993 from two studies, although the sharing of alleles was greatest from brother-brother pairs in one study, and sister-sister in the other. Data from the Irish schizophrenia study was also submitted, with no strong evidence for linkage on the X chromosome. For bipolar disease, following the report of a Finnish family linked to Xq24-q27, the Columbia group reported some positive results for this region from 57 families, however, another group found no evidence for linkage to this region. Of interest, is the clustering of low positive linkage results that point to regions for possible further study. PMID:9686435

  7. Chromosome analysis and sorting

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Kubaláková, Marie; Suchánková, Pavla; Kovářová, Pavlína; Bartoš, Jan; Šimková, Hana

    Weinheim : Wiley-VCH, 2007 - (Doležel, J.; Greilhuber, J.; Suda, J.), s. 373-403 ISBN 978-3-527-31487-4 R&D Projects: GA ČR GA521/04/0607; GA ČR GP521/05/P257; GA ČR GD521/05/H013; GA MŠk(CZ) LC06004 Grant ostatní: Mendelova zemědělská a lesnická univerzita v Brně / Agronomická fakulta(CZ) ME 844 Institutional research plan: CEZ:AV0Z5038910 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje Keywords : Plant flow cytometry * chromosome sorting * flow cytogenetics Subject RIV: EB - Genetics ; Molecular Biology http://books. google .com/books?id=3cwakORieqUC&pg=PA373&lpg=PA373&dq=Chromosome+analysis+and+sorting&source=web&ots=8IyvJlBQyq&sig=_NlXyQQgBCwpj1pTC9YITvvVZqU

  8. Airway basal stem cells: a perspective on their roles in epithelial homeostasis and remodeling.

    Science.gov (United States)

    Rock, Jason R; Randell, Scott H; Hogan, Brigid L M

    2010-01-01

    The small airways of the human lung undergo pathological changes in pulmonary disorders, such as chronic obstructive pulmonary disease (COPD), asthma, bronchiolitis obliterans and cystic fibrosis. These clinical problems impose huge personal and societal healthcare burdens. The changes, termed 'pathological airway remodeling', affect the epithelium, the underlying mesenchyme and the reciprocal trophic interactions that occur between these tissues. Most of the normal human airway is lined by a pseudostratified epithelium of ciliated cells, secretory cells and 6-30% basal cells, the proportion of which varies along the proximal-distal axis. Epithelial abnormalities range from hypoplasia (failure to differentiate) to basal- and goblet-cell hyperplasia, squamous- and goblet-cell metaplasia, dysplasia and malignant transformation. Mesenchymal alterations include thickening of the basal lamina, smooth muscle hyperplasia, fibrosis and inflammatory cell accumulation. Paradoxically, given the prevalence and importance of airway remodeling in lung disease, its etiology is poorly understood. This is due, in part, to a lack of basic knowledge of the mechanisms that regulate the differentiation, maintenance and repair of the airway epithelium. Specifically, little is known about the proliferation and differentiation of basal cells, a multipotent stem cell population of the pseudostratified airway epithelium. This Perspective summarizes what we know, and what we need to know, about airway basal cells to evaluate their contributions to normal and abnormal airway remodeling. We contend that exploiting well-described model systems using both human airway epithelial cells and the pseudostratified epithelium of the genetically tractable mouse trachea will enable crucial discoveries regarding the pathogenesis of airway disease. PMID:20699479

  9. Mandibular remodeling measured on cephalograms. 1. Osseous changes relative to superimposition on metallic implants.

    Science.gov (United States)

    Baumrind, S; Ben-Bassat, Y; Korn, E L; Bravo, L A; Curry, S

    1992-08-01

    We report the results of a study aimed at quantifying remodeling of mandibular surfaces in a sample of growing children who represent those usually treated by orthodontists in the mixed and early adult dentition. The sample, 31 patients with metallic implants of the Björk-type, was monitored at annual intervals between 8 1/2 and 15 1/2 years of age. (Maxillary remodeling changes for the sample have been reported earlier.) The present article reports findings concerning changes at condyle, gonion, menton, pogonion, and point B as identified on lateral cephalograms. Data are reported in the Frankfort plane frame of reference with the cephalograms from different time points superimposed on the metallic implants. Mean displacement at condyle was larger than that at any other landmark and was similar in magnitude and direction to the observations of Björk when the difference in orientation of the vertical axis in the two studies is taken into account. The mean displacement of gonion was in an upward and backward direction at an angle of approximately 45 degrees to the Frankfort plane. Mean displacements at menton and pogonion were in a downward and backward direction but were very small. Mean displacement at point B was somewhat greater than that of menton and gonion, oriented in an upward and backward direction. Individual variation for most of the parameters measured was sufficiently large to warrant the inference that caution should be used when mean values are applied to the analysis of individual cases. PMID:1636630

  10. Detecting airway remodeling in COPD and emphysema using low-dose CT imaging

    Science.gov (United States)

    Rudyanto, R.; Ceresa, M.; Muñoz-Barrutia, A.; Ortiz-de-Solorzano, C.

    2012-03-01

    In this study, we quantitatively characterize lung airway remodeling caused by smoking-related emphysema and Chronic Obstructive Pulmonary Disease (COPD), in low-dose CT scans. To that end, we established three groups of individuals: subjects with COPD (n=35), subjects with emphysema (n=38) and healthy smokers (n=28). All individuals underwent a low-dose CT scan, and the images were analyzed as described next. First the lung airways were segmented using a fast marching method and labeled according to its generation. Along each airway segment, cross-section images were resampled orthogonal to the airway axis. Next 128 rays were cast from the center of the airway lumen in each crosssection slice. Finally, we used an integral-based method, to measure lumen radius, wall thickness, mean wall percentage and mean peak wall attenuation on every cast ray. Our analysis shows that both the mean global wall thickness and the lumen radius of the airways of both COPD and emphysema groups were significantly different from those of the healthy group. In addition, the wall thickness change starts at the 3rd airway generation in the COPD patients compared with emphysema patients, who display the first significant changes starting in the 2nd generation. In conclusion, it is shown that airway remodeling happens in individuals suffering from either COPD or emphysema, with some local difference between both groups, and that we are able to detect and accurately quantify this process using images of low-dose CT scans.

  11. The chromatin remodeler SPLAYED regulates specific stress signaling pathways.

    Directory of Open Access Journals (Sweden)

    Justin W Walley

    2008-12-01

    Full Text Available Organisms are continuously exposed to a myriad of environmental stresses. Central to an organism's survival is the ability to mount a robust transcriptional response to the imposed stress. An emerging mechanism of transcriptional control involves dynamic changes in chromatin structure. Alterations in chromatin structure are brought about by a number of different mechanisms, including chromatin modifications, which covalently modify histone proteins; incorporation of histone variants; and chromatin remodeling, which utilizes ATP hydrolysis to alter histone-DNA contacts. While considerable insight into the mechanisms of chromatin remodeling has been gained, the biological role of chromatin remodeling complexes beyond their function as regulators of cellular differentiation and development has remained poorly understood. Here, we provide genetic, biochemical, and biological evidence for the critical role of chromatin remodeling in mediating plant defense against specific biotic stresses. We found that the Arabidopsis SWI/SNF class chromatin remodeling ATPase SPLAYED (SYD is required for the expression of selected genes downstream of the jasmonate (JA and ethylene (ET signaling pathways. SYD is also directly recruited to the promoters of several of these genes. Furthermore, we show that SYD is required for resistance against the necrotrophic pathogen Botrytis cinerea but not the biotrophic pathogen Pseudomonas syringae. These findings demonstrate not only that chromatin remodeling is required for selective pathogen resistance, but also that chromatin remodelers such as SYD can regulate specific pathways within biotic stress signaling networks.

  12. Cohesin in determining chromosome architecture

    Energy Technology Data Exchange (ETDEWEB)

    Haering, Christian H., E-mail: christian.haering@embl.de [Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg (Germany); Jessberger, Rolf, E-mail: rolf.jessberger@tu-dresden.de [Institute of Physiological Chemistry, Dresden University of Technology, Dresden (Germany)

    2012-07-15

    Cells use ring-like structured protein complexes for various tasks in DNA dynamics. The tripartite cohesin ring is particularly suited to determine chromosome architecture, for it is large and dynamic, may acquire different forms, and is involved in several distinct nuclear processes. This review focuses on cohesin's role in structuring chromosomes during mitotic and meiotic cell divisions and during interphase.

  13. Causes of oncogenic chromosomal translocation

    OpenAIRE

    Aplan, Peter D.

    2005-01-01

    Non-random chromosomal translocations are frequently associated with a variety of cancers, especially hematologic malignancies and childhood sarcomas In addition to their diagnostic utility, chromosomal translocations are increasingly being used in the clinic to guide therapeutic decisions. However, the mechanisms which cause these translocations remain poorly understood. Illegit...

  14. Remodeling of endogenous mammary epithelium by breast cancer stem cells.

    Science.gov (United States)

    Parashurama, Natesh; Lobo, Neethan A; Ito, Ken; Mosley, Adriane R; Habte, Frezghi G; Zabala, Maider; Smith, Bryan R; Lam, Jessica; Weissman, Irving L; Clarke, Michael F; Gambhir, Sanjiv S

    2012-10-01

    Poorly regulated tissue remodeling results in increased breast cancer risk, yet how breast cancer stem cells (CSC) participate in remodeling is unknown. We performed in vivo imaging of changes in fluorescent, endogenous duct architecture as a metric for remodeling. First, we quantitatively imaged physiologic remodeling of primary branches of the developing and regenerating mammary tree. To assess CSC-specific remodeling events, we isolated CSC from MMTV-Wnt1 (mouse mammary tumor virus long-term repeat enhancer driving Wnt1 oncogene) breast tumors, a well studied model in which tissue remodeling affects tumorigenesis. We confirm that CSC drive tumorigenesis, suggesting a link between CSC and remodeling. We find that normal, regenerating, and developing gland maintain a specific branching pattern. In contrast, transplantation of CSC results in changes in the branching patterns of endogenous ducts while non-CSC do not. Specifically, in the presence of CSC, we identified an increased number of branches, branch points, ducts which have greater than 40 branches (5/33 for CSC and 0/39 for non-CSC), and histological evidence of increased branching. Moreover, we demonstrate that only CSC implants invade into surrounding stroma with structures similar to developing mammary ducts (nine for CSC and one for non-CSC). Overall, we demonstrate a novel approach for imaging physiologic and pathological remodeling. Furthermore, we identify unique, CSC-specific, remodeling events. Our data suggest that CSC interact with the microenvironment differently than non-CSC, and that this could eventually be a therapeutic approach for targeting CSC. PMID:22899386

  15. Genetics Home Reference: ring chromosome 20 syndrome

    Science.gov (United States)

    ... 3 links) Encyclopedia: Chromosome Encyclopedia: Epilepsy Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 20 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  16. Genetics Home Reference: ring chromosome 14 syndrome

    Science.gov (United States)

    ... Encyclopedia: Chromosome Health Topic: Developmental Disabilities Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 14 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  17. Bacterial chromosome organization and segregation.

    Science.gov (United States)

    Badrinarayanan, Anjana; Le, Tung B K; Laub, Michael T

    2015-01-01

    If fully stretched out, a typical bacterial chromosome would be nearly 1 mm long, approximately 1,000 times the length of a cell. Not only must cells massively compact their genetic material, but they must also organize their DNA in a manner that is compatible with a range of cellular processes, including DNA replication, DNA repair, homologous recombination, and horizontal gene transfer. Recent work, driven in part by technological advances, has begun to reveal the general principles of chromosome organization in bacteria. Here, drawing on studies of many different organisms, we review the emerging picture of how bacterial chromosomes are structured at multiple length scales, highlighting the functions of various DNA-binding proteins and the impact of physical forces. Additionally, we discuss the spatial dynamics of chromosomes, particularly during their segregation to daughter cells. Although there has been tremendous progress, we also highlight gaps that remain in understanding chromosome organization and segregation. PMID:26566111

  18. Genome comparisons reveal a dominant mechanism of chromosome number reduction in grasses and accelerated genome evolution in Triticeae

    Science.gov (United States)

    Luo, M. C.; Deal, K. R.; Akhunov, E. D.; Akhunova, A. R.; Anderson, O. D.; Anderson, J. A.; Blake, N.; Clegg, M. T.; Coleman-Derr, D.; Conley, E. J.; Crossman, C. C.; Dubcovsky, J.; Gill, B. S.; Gu, Y. Q.; Hadam, J.; Heo, H. Y.; Huo, N.; Lazo, G.; Ma, Y.; Matthews, D. E.; McGuire, P. E.; Morrell, P. L.; Qualset, C. O.; Renfro, J.; Tabanao, D.; Talbert, L. E.; Tian, C.; Toleno, D. M.; Warburton, M. L.; You, F. M.; Zhang, W.; Dvorak, J.

    2009-01-01

    Single-nucleotide polymorphism was used in the construction of an expressed sequence tag map of Aegilops tauschii, the diploid source of the wheat D genome. Comparisons of the map with the rice and sorghum genome sequences revealed 50 inversions and translocations; 2, 8, and 40 were assigned respectively to the rice, sorghum, and Ae. tauschii lineages, showing greatly accelerated genome evolution in the large Triticeae genomes. The reduction of the basic chromosome number from 12 to 7 in the Triticeae has taken place by a process during which an entire chromosome is inserted by its telomeres into a break in the centromeric region of another chromosome. The original centromere–telomere polarity of the chromosome arms is maintained in the new chromosome. An intrachromosomal telomere–telomere fusion resulting in a pericentric translocation of a chromosome segment or an entire arm accompanied or preceded the chromosome insertion in some instances. Insertional dysploidy has been recorded in three grass subfamilies and appears to be the dominant mechanism of basic chromosome number reduction in grasses. A total of 64% and 66% of Ae. tauschii genes were syntenic with sorghum and rice genes, respectively. Synteny was reduced in the vicinity of the termini of modern Ae. tauschii chromosomes but not in the vicinity of the ancient termini embedded in the Ae. tauschii chromosomes, suggesting that the dependence of synteny erosion on gene location along the centromere–telomere axis either evolved recently in the Triticeae phylogenetic lineage or its evolution was recently accelerated. PMID:19717446

  19. Osteoblast recruitment routes in human cancellous bone remodeling

    DEFF Research Database (Denmark)

    Kristensen, Helene B; Levin Andersen, Thomas; Marcussen, Niels;

    2014-01-01

    It is commonly proposed that bone forming osteoblasts recruited during bone remodeling originate from bone marrow perivascular cells, bone remodeling compartment canopy cells, or bone lining cells. However, an assessment of osteoblast recruitment during adult human cancellous bone remodeling is...... lacking. We addressed this question by quantifying cell densities, cell proliferation, osteoblast differentiation markers, and capillaries in human iliac crest biopsy specimens. We found that recruitment occurs on both reversal and bone-forming surfaces, as shown by the cell density and osterix levels on...

  20. Development of a two-parameter slit-scan flow cytometer for screening of normal and aberrant chromosomes: application to a karyotype of Sus scrofa domestica (pig)

    Science.gov (United States)

    Hausmann, Michael; Doelle, Juergen; Arnold, Armin; Stepanow, Boris; Wickert, Burkhard; Boscher, Jeannine; Popescu, Paul C.; Cremer, Christoph

    1992-07-01

    Laser fluorescence activated slit-scan flow cytometry offers an approach to a fast, quantitative characterization of chromosomes due to morphological features. It can be applied for screening of chromosomal abnormalities. We give a preliminary report on the development of the Heidelberg slit-scan flow cytometer. Time-resolved measurement of the fluorescence intensity along the chromosome axis can be registered simultaneously for two parameters when the chromosome axis can be registered simultaneously for two parameters when the chromosome passes perpendicularly through a narrowly focused laser beam combined by a detection slit in the image plane. So far automated data analysis has been performed off-line on a PC. In its final performance, the Heidelberg slit-scan flow cytometer will achieve on-line data analysis that allows an electro-acoustical sorting of chromosomes of interest. Interest is high in the agriculture field to study chromosome aberrations that influence the size of litters in pig (Sus scrofa domestica) breeding. Slit-scan measurements have been performed to characterize chromosomes of pigs; we present results for chromosome 1 and a translocation chromosome 6/15.

  1. ADN et chromosomes

    OpenAIRE

    Hayes, Hélène

    2000-01-01

    Chaque chromosome contient une seule molécule d’ADN. L’ADN déroulé d’un noyau de cellule humaine mesurerait environ 1,8 m : chaque molécule d’ADN est enroulée et compactée en plusieurs étapes, grâce à l’association de différentes protéines, et loge dans le noyau de 6 µm de diamètre. Le degré de condensation de l’ADN est variable selon les régions chromosomiques et les régions les moins condensées sont les plus riches en gènes. L’ADN est composé d’une variété de séquences codantes ou non et ré...

  2. X-Chromosome dosage compensation.

    Science.gov (United States)

    Meyer, Barbara J

    2005-01-01

    In mammals, flies, and worms, sex is determined by distinctive regulatory mechanisms that cause males (XO or XY) and females (XX) to differ in their dose of X chromosomes. In each species, an essential X chromosome-wide process called dosage compensation ensures that somatic cells of either sex express equal levels of X-linked gene products. The strategies used to achieve dosage compensation are diverse, but in all cases, specialized complexes are targeted specifically to the X chromosome(s) of only one sex to regulate transcript levels. In C. elegans, this sex-specific targeting of the dosage compensation complex (DCC) is controlled by the same developmental signal that establishes sex, the ratio of X chromosomes to sets of autosomes (X:A signal). Molecular components of this chromosome counting process have been defined. Following a common step of regulation, sex determination and dosage compensation are controlled by distinct genetic pathways. C. elegans dosage compensation is implemented by a protein complex that binds both X chromosomes of hermaphrodites to reduce transcript levels by one-half. The dosage compensation complex resembles the conserved 13S condensin complex required for both mitotic and meiotic chromosome resolution and condensation, implying the recruitment of ancient proteins to the new task of regulating gene expression. Within each C. elegans somatic cell, one of the DCC components also participates in the separate mitotic/meiotic condensin complex. Other DCC components play pivotal roles in regulating the number and distribution of crossovers during meiosis. The strategy by which C. elegans X chromosomes attract the condensin-like DCC is known. Small, well-dispersed X-recognition elements act as entry sites to recruit the dosage compensation complex and to nucleate spreading of the complex to X regions that lack recruitment sites. In this manner, a repressed chromatin state is spread in cis over short or long distances, thus establishing the

  3. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the continued development of a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and...

  4. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and inversions) have profound genetic...

  5. Identification by R-banding and FISH of chromosome arms involved in Robertsonian translocations in several deer species

    OpenAIRE

    Bonnet-Garnier, Amelie; Claro, F.; Thevenon, S.; Gautier, Mathieu; Hayes, Hélène

    2003-01-01

    We constructed and analyzed the RBG-banded karyotype of ¢ve deer species: Chital (Axis axis), White-lipped deer (Cervus albirostris), Rusa deer (Cervus timorensis russa), Sambar deer (Cervus unicolor) and Eld’s deer (Cervus eldi siamensis). Among these ¢ve species, only Eld’s deer had been previously karyotyped using R-banding. In order to identify all the chromosome correspondences with cattle and precisely which chromosome arms are involved in Robertsonian translocations, we compared the ka...

  6. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  7. Mitotic chromosome condensation in vertebrates

    International Nuclear Information System (INIS)

    Work from several laboratories over the past 10–15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292–301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories—a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307–316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119–1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579–589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different

  8. Mammary remodelling and metabolic activity in dairy goats

    DEFF Research Database (Denmark)

    Safayi, Sina

    ) differences between PP and MP animals with respect to milk production and lactation persistency may be related to differences in mammary growth and remodelling also during lactation, 2) the factors responsible for interfering with mammary remodelling in continuous lactation throughout the dry period into the...... present thesis aimed to address the hypotheses that 1) differences between PP and MP animals with respect to milk production and lactation persistency may be related to differences in mammary growth and remodelling also during lactation, 2) the factors responsible for interfering with mammary remodelling...... be effectively renewed as one lactation comes to an end and prior to onset of the next lactation. Generally, the level of milk production and the changes in milk yield over the course of lactation depend on three main factors: 1) the number of MEC, which in turn is affected by the balance between the...

  9. A gene-centric study of common carotid artery remodelling

    NARCIS (Netherlands)

    Harrison, Seamus C.; Zabaneh, Delilah; Asselbergs, Folkert W.; Drenos, Fotios; Jones, Gregory T.; Shah, Sonia; Gertow, Karl; Sennblad, Bengt; Strawbridge, Rona J.; Gigante, Bruna; Holewijn, Suzanne; De Graaf, Jacqueline; Vermeulen, Sita; Folkersen, Lasse; van Rij, Andre M.; Baldassarre, Damiano; Veglia, Fabrizio; Talmud, Philippa J.; Deanfield, John E.; Agu, Obi; Kivimaki, Mika; Kumari, Meena; Bown, Matthew J.; Nyyssonen, Kristiina; Rauramaa, Rainer; Smit, Andries J.; Franco-Cereceda, Anders; Giral, Philippe; Mannarino, Elmo; Silveira, Angela; Syvanen, Ann-Christine; de Borst, Gert J.; van der Graaf, Yolanda; de Faire, Ulf; Baas, Annette F.; Blankensteijn, Jan D.; Wareham, Nicholas J.; Fowkes, Gerry; Tzoulaki, Ionna; Price, Jacqueline F.; Tremoli, Elena; Hingorani, Aroon D.; Eriksson, Per; Hamsten, Anders; Humphries, Steve E.

    2013-01-01

    Background: Expansive remodelling is the process of compensatory arterial enlargement in response to atherosclerotic stimuli. The genetic determinants of this process are poorly characterized. Methods: Genetic association analyses of inter-adventitial common carotid artery diameter (ICCAD) in the IM

  10. Nitric Oxide and Hydrogen Sulfide Regulation of Ischemic Vascular Remodeling.

    Science.gov (United States)

    Yuan, Shuai; Kevil, Christopher G

    2016-02-01

    Blockage or restriction of blood flow through conduit arteries results in tissue ischemia downstream of the disturbed area. Local tissues can adapt to this challenge by stimulating vascular remodeling through angiogenesis and arteriogenesis thereby restoring blood perfusion and removal of wastes. Multiple molecular mechanisms of vascular remodeling during ischemia have been identified and extensively studied. However, therapeutic benefits from these findings and insights are limited due to the complexity of various signaling networks and a lack of understanding central metabolic regulators governing these responses. The gasotransmitters NO and H2 S have emerged as master regulators that influence multiple molecular targets necessary for ischemic vascular remodeling. In this review, we discuss how NO and H2 S are individually regulated under ischemia, what their roles are in angiogenesis and arteriogenesis, and how their interaction controls ischemic vascular remodeling. PMID:26381654

  11. Cutaneous remodeling and photorejuvenation using radiofrequency devices

    Directory of Open Access Journals (Sweden)

    Elsaie Mohamed

    2009-01-01

    Full Text Available Radio frequency (RF is electromagnetic radiation in the frequency range of 3-300GHz. The primary effects of RF energy on living tissue are considered to be thermal. The goal of the new devices based on these frequency ranges is to heat specific layers of the skin. The directed use of RF can induce dermal heating and cause collagen degeneration. Wound healing mechanisms promote the remodeling of collagen and wound contraction, which ultimately clinically enhances the appearance of mild to moderate skin laxity. Preliminary studies have reported efficacy in the treatment of laxity that involves the periorbital area and jowls. Because RF energy is not dependent on specific chromophore interaction, epidermal melanin is not at risk of destruction and treatment of all skin types is possible. As such, radiofrequency-based systems have been used successfully for nonablative skin rejuvenation, atrophic scar revision and treatment of unwanted hair, vascular lesions and inflammatory acne. The use of RF is becoming more popular, although a misunderstanding exists regarding the mechanisms and limitations of its actions. This concise review serves as an introduction and guide to many aspects of RF in the non ablative rejuvenation of skin.

  12. Remodeling of alveolar septa after murine pneumonectomy.

    Science.gov (United States)

    Ysasi, Alexandra B; Wagner, Willi L; Bennett, Robert D; Ackermann, Maximilian; Valenzuela, Cristian D; Belle, Janeil; Tsuda, Akira; Konerding, Moritz A; Mentzer, Steven J

    2015-06-15

    In most mammals, removing one lung (pneumonectomy) results in the compensatory growth of the remaining lung. In mice, stereological observations have demonstrated an increase in the number of mature alveoli; however, anatomic evidence of the early phases of alveolar growth has remained elusive. To identify changes in the lung microstructure associated with neoalveolarization, we used tissue histology, electron microscopy, and synchrotron imaging to examine the configuration of the alveolar duct after murine pneumonectomy. Systematic histological examination of the cardiac lobe demonstrated no change in the relative frequency of dihedral angle components (Ends, Bends, and Junctions) (P > 0.05), but a significant decrease in the length of a subset of septal ends ("E"). Septal retraction, observed in 20-30% of the alveolar ducts, was maximal on day 3 after pneumonectomy (P alveolar duct diameter ratio (Dout:Din) was significantly lower 3 days after pneumonectomy compared to all controls except for the detergent-treated lung (P surface tension within the alveolar duct, resulting in a new equilibrium at a higher total energy and lower surface area. The spatial and temporal association of these microstructural changes with postpneumonectomy lung growth suggests that these changes represent an early phase of alveolar duct remodeling. PMID:26078396

  13. Gametocidal chromosomes enhancing chromosome aberration in common wheat induced by 5-azacytidine.

    Science.gov (United States)

    Su, W-Y; Cong, W-W; Shu, Y-J; Wang, D; Xu, G-H; Guo, C-H

    2013-01-01

    The gametocidal (Gc) chromosome from Aegilops spp induces chromosome mutation, which is introduced into common wheat as a tool of chromosome manipulation for genetic improvement. The Gc chromosome functions similar to a restriction-modification system in bacteria, in which DNA methylation is an important regulator. We treated root tips of wheat carrying Gc chromosomes with the hypomethylation agent 5-azacytidine; chromosome breakage and micronuclei were observed in these root tips. The frequency of aberrations differed in wheat containing different Gc chromosomes, suggesting different functions inducing chromosome breakage. Gc chromosome 3C caused the greatest degree of chromosome aberration, while Gc chromosome 3C(SAT) and 2C caused only slight chromosome aberration. Gc chromosome 3C induced different degrees of chromosome aberration in wheat varieties Triticum aestivum var. Chinese Spring and Norin 26, demonstrating an inhibition function in common wheat. PMID:23884766

  14. Remodeling of the bone material containing microcracks: A theoretical analysis

    Science.gov (United States)

    Ramtani, S.; Zidi, M.

    1999-12-01

    The question is, what happens when the bone loses its ability for load-driven adaptation, when damage is no longer repaired as it seems to be the case for bone loss associated with age, medication or disease? In this study, we tempt to show how damage can influence the remodeling process. A thermodynamic theoretical framework is therefore provided as a basis for a consistent formulation of bone remodeling involving a chemical reaction and mass transfer between two constituents in presence of microcracks.

  15. Collagen scaffold remodeling by human mesenchymal stem cells

    OpenAIRE

    Han, SJ; Chan, BP

    2011-01-01

    Type I collagen has been widely used as scaffold for tissue engineering because of its excellent biocompatibility and negligible immunogenicity. We previously have developed a collagen microencapsulation technology entrapping many cells including human mesenchymal stem cells (hMSCs) in microspheres made of nanofibrous collagen meshwork. Nevertheless, little is understood about how stem cells interact with and remodel the collagen meshwork. This study aims to investigate collagen remodeling by...

  16. The relationship between eosinophilia and airway remodelling in mild asthma

    OpenAIRE

    Wilson, S J; Rigden, H.M.; Ward, J. A.; Laviolette, M.; Jarjour, N N; Djukanović, R.

    2013-01-01

    Background Eosinophilia is a marker of corticosteroid responsiveness and risk of exacerbation in asthma; although it has been linked to submucosal matrix deposition, its relationship with other features of airway remodelling is less clear. Objective The aim of this study was to investigate the relationship between airway eosinophilia and airway remodelling. Methods Bronchial biopsies from subjects (n = 20 in each group) with mild steroid-naïve asthma, with either low (0–0....

  17. Chromosome conservation in squamate reptiles revealed by comparative chromosome painting

    Czech Academy of Sciences Publication Activity Database

    Giovannotti, M.; Pokorná, Martina; Kratochvíl, L.; Caputo, V.; Olmo, E.; Ferguson-Smith, M. A.; Rens, W.

    Manchester : ICCS, 2011. 78-78. [Intarnational Chromosome Conference /18./. 29.08.2011-02.09.2011, Manchester] Institutional research plan: CEZ:AV0Z50450515 Keywords : squamate reptiles Subject RIV: EG - Zoology

  18. Numerous transitions of sex chromosomes in Diptera.

    Directory of Open Access Journals (Sweden)

    Beatriz Vicoso

    2015-04-01

    Full Text Available Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot, but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes. Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa.

  19. Cell Matrix Remodeling Ability Shown by Image Spatial Correlation

    Directory of Open Access Journals (Sweden)

    Chi-Li Chiu

    2013-01-01

    Full Text Available Extracellular matrix (ECM remodeling is a critical step of many biological and pathological processes. However, most of the studies to date lack a quantitative method to measure ECM remodeling at a scale comparable to cell size. Here, we applied image spatial correlation to collagen second harmonic generation (SHG images to quantitatively evaluate the degree of collagen remodeling by cells. We propose a simple statistical method based on spatial correlation functions to determine the size of high collagen density area around cells. We applied our method to measure collagen remodeling by two breast cancer cell lines (MDA-MB-231 and MCF-7, which display different degrees of invasiveness, and a fibroblast cell line (NIH/3T3. We found distinct collagen compaction levels of these three cell lines by applying the spatial correlation method, indicating different collagen remodeling ability. Furthermore, we quantitatively measured the effect of Latrunculin B and Marimastat on MDA-MB-231 cell line collagen remodeling ability and showed that significant collagen compaction level decreases with these treatments.

  20. Familial transmission of a deletion of chromosome 21 derived from a translocation between chromosome 21 and an inverted chromosome 22.

    Science.gov (United States)

    Aviv, H; Lieber, C; Yenamandra, A; Desposito, F

    1997-06-27

    Chromosome analysis of a newborn boy with Down syndrome resulted in the identification of a family with an unusual derivative chromosome 22. The child has 46 chromosomes, including two chromosomes 21, one normal chromosome 22, and a derivative chromosome 22. Giemsa banding and fluorescent in situ hybridization (FISH) studies show that the derivative chromosome is chromosome 22 with evidence of both paracentric and pericentric inversions, joined to the long arm of chromosome 21 from 21q21.2 to qter. The rearrangement results in partial trisomy 21 extending from 21q21.2 to 21q terminus in the patient. The child's mother, brother, maternal aunt, and maternal grandmother are all carriers of the derivative chromosome. All have 45 chromosomes, with one normal chromosome 21, one normal chromosome 22, and the derivative chromosome 22. The rearrangement results in the absence of the short arm, the centromere, and the proximal long arm of chromosome 21 (del 21pter-21q21.2) in carriers. Carriers of the derivative chromosome in this family have normal physical appearance, mild learning disabilities and poor social adjustment. PMID:9182781

  1. Meiosis and chromosome painting of sex chromosome systems in Ceboidea.

    Science.gov (United States)

    Mudry, M D; Rahn, I M; Solari, A J

    2001-06-01

    The identity of the chromosomes involved in the multiple sex system of Alouatta caraya (Aca) and the possible distribution of this system among other Ceboidea were investigated by chromosome painting of mitotic cells from five species and by analysis of meiosis at pachytene in two species. The identity of the autosome #7 (X2) involved in the multiple system of Aca and its breakage points were demonstrated by both meiosis and chromosome painting. These features are identical to those described by Consigliere et al. [1996] in Alouatta seniculus sara (Assa) and Alouatta seniculus arctoidea (Asar). This multiple system was absent in the other four Ceboidea species studied here. However, data from the literature strongly suggest the presence of this multiple in other members of this genus. The presence of this multiple system among several species and subspecies that show high levels of chromosome rearrangements may suggest a special selective value of this multiple. The meiotic features of the sex systems of Aca and Cebus apella paraguayanus (Cap) are strikingly different at pachytene, as the latter system is similar to the sex pair of man and other primates. The relatively large genetic distances between species presently showing this multiple system suggest that its origin is not recent. Other members of the same genus should be investigated at meiosis and by chromosome painting in order to know the extent and distribution of this complex sex-chromosome system. PMID:11376445

  2. Introductory lecture on triple-axis spectrometer

    International Nuclear Information System (INIS)

    Triple-axis spectrometer is a multi-purpose instrument for powder neutron diffraction, single crystal neutron diffraction, powder inelastic neutron scattering, single crystal inelastic neutron scattering, and neutron polarization analysis. In this lecture how to use the triple-axis spectrometer is explained for the beginners. (author)

  3. Chromosome fragility in Freemartin cattle

    Directory of Open Access Journals (Sweden)

    V. Barbieri

    2010-04-01

    Full Text Available The aim of the present study was to verify chromosome fragility in freemartin cattle using chromosome aberration (CA and sister chromatid exchange (SCE tests. A total of eighteen co-twins were investigated. Fourteen animals were identified as cytogenetically chimeric (2n=60, XX/XY while 4 were classified as normal. Freemartin cattle showed a higher percentage of aneuploid cells (18.64% and highly significant statistical differences (P < 0.001 in mean values of gaps (4.53 ± 2.05, chromatid breaks (0.26 ± 0.51, and significant statistical differences (P < 0.005 in mean values of chromosome breaks (0.12 ± 0.43 when compared to 10 control animals from single births (aneuploid cells, 11.20%; gaps, 2.01 ± 1.42; chromatid breaks, 0.05 ± 0.22; chromosome breaks, 0.02 ± 0.14.

  4. Adaptive scapula bone remodeling computational simulation: Relevance to regenerative medicine

    International Nuclear Information System (INIS)

    Shoulder arthroplasty success has been attributed to many factors including, bone quality, soft tissue balancing, surgeon experience, and implant design. Improved long-term success is primarily limited by glenoid implant loosening. Prosthesis design examines materials and shape and determines whether the design should withstand a lifetime of use. Finite element (FE) analyses have been extensively used to study stresses and strains produced in implants and bone. However, these static analyses only measure a moment in time and not the adaptive response to the altered environment produced by the therapeutic intervention. Computational analyses that integrate remodeling rules predict how bone will respond over time. Recent work has shown that subject-specific two- and three dimensional adaptive bone remodeling models are feasible and valid. Feasibility and validation were achieved computationally, simulating bone remodeling using an intact human scapula, initially resetting the scapular bone material properties to be uniform, numerically simulating sequential loading, and comparing the bone remodeling simulation results to the actual scapula’s material properties. Three-dimensional scapula FE bone model was created using volumetric computed tomography images. Muscle and joint load and boundary conditions were applied based on values reported in the literature. Internal bone remodeling was based on element strain-energy density. Initially, all bone elements were assigned a homogeneous density. All loads were applied for 10 iterations. After every iteration, each bone element’s remodeling stimulus was compared to its corresponding reference stimulus and its material properties modified. The simulation achieved convergence. At the end of the simulation the predicted and actual specimen bone apparent density were plotted and compared. Location of high and low predicted bone density was comparable to the actual specimen. High predicted bone density was greater than

  5. Adaptive scapula bone remodeling computational simulation: Relevance to regenerative medicine

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Gulshan B., E-mail: gbsharma@ucalgary.ca [Emory University, Department of Radiology and Imaging Sciences, Spine and Orthopaedic Center, Atlanta, Georgia 30329 (United States); University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213 (United States); University of Calgary, Schulich School of Engineering, Department of Mechanical and Manufacturing Engineering, Calgary, Alberta T2N 1N4 (Canada); Robertson, Douglas D., E-mail: douglas.d.robertson@emory.edu [Emory University, Department of Radiology and Imaging Sciences, Spine and Orthopaedic Center, Atlanta, Georgia 30329 (United States); University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213 (United States)

    2013-07-01

    Shoulder arthroplasty success has been attributed to many factors including, bone quality, soft tissue balancing, surgeon experience, and implant design. Improved long-term success is primarily limited by glenoid implant loosening. Prosthesis design examines materials and shape and determines whether the design should withstand a lifetime of use. Finite element (FE) analyses have been extensively used to study stresses and strains produced in implants and bone. However, these static analyses only measure a moment in time and not the adaptive response to the altered environment produced by the therapeutic intervention. Computational analyses that integrate remodeling rules predict how bone will respond over time. Recent work has shown that subject-specific two- and three dimensional adaptive bone remodeling models are feasible and valid. Feasibility and validation were achieved computationally, simulating bone remodeling using an intact human scapula, initially resetting the scapular bone material properties to be uniform, numerically simulating sequential loading, and comparing the bone remodeling simulation results to the actual scapula’s material properties. Three-dimensional scapula FE bone model was created using volumetric computed tomography images. Muscle and joint load and boundary conditions were applied based on values reported in the literature. Internal bone remodeling was based on element strain-energy density. Initially, all bone elements were assigned a homogeneous density. All loads were applied for 10 iterations. After every iteration, each bone element’s remodeling stimulus was compared to its corresponding reference stimulus and its material properties modified. The simulation achieved convergence. At the end of the simulation the predicted and actual specimen bone apparent density were plotted and compared. Location of high and low predicted bone density was comparable to the actual specimen. High predicted bone density was greater than

  6. Methods for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1995-01-01

    Methods and compositions for chromosome-specific staining are provided. Compositions comprise heterogenous mixtures of labeled nucleic acid fragments having substantially complementary base sequences to unique sequence regions of the chromosomal DNA for which their associated staining reagent is specific. Methods include methods for making the chromosome-specific staining compositions of the invention, and methods for applying the staining compositions to chromosomes.

  7. Chromosome Architecture and Genome Organization

    OpenAIRE

    Giorgio Bernardi

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few...

  8. Chromosome evolution in Neotropical butterflies

    OpenAIRE

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O.; Brown, Keith S., Jr.

    2013-01-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results i...

  9. A novel microtubule-modulating agent EM011 inhibits angiogenesis by repressing the HIF-1α axis and disrupting cell polarity and migration

    OpenAIRE

    Karna, Prasanthi; Rida, Padmashree C. G.; Turaga, Ravi Chakra; Gao, Jinmin; Gupta, Meenakshi; Fritz, Andreas; Werner, Erica; Yates, Clayton; Zhou, Jun; Aneja, Ritu

    2012-01-01

    Endothelial tubular morphogenesis relies on an exquisite interplay of microtubule dynamics and actin remodeling to propel directed cell migration. Recently, the dynamicity and integrity of microtubules have been implicated in the trafficking and efficient translation of the mRNA for HIF-1α (hypoxia-inducible factor), the master regulator of tumor angiogenesis. Thus, microtubule-disrupting agents that perturb the HIF-1α axis and neovascularization cascade are attractive anticancer drug candida...

  10. Numerically abnormal chromosome constitutions in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    Chapter 24, discusses numerically abnormal chromosome constitutions in humans. This involves abnormalities of human chromosome number, including polyploidy (when the number of sets of chromosomes increases) and aneuploidy (when the number of individual normal chromosomes changes). Chapter sections discuss the following chromosomal abnormalities: human triploids, imprinting and uniparental disomy, human tetraploids, hydatidiform moles, anomalies caused by chromosomal imbalance, 13 trisomy (D{sub 1} trisomy, Patau syndrome), 21 trisomy (Down syndrome), 18 trisomy syndrome (Edwards syndrome), other autosomal aneuploidy syndromes, and spontaneous abortions. The chapter concludes with remarks on the nonrandom participation of chromosomes in trisomy. 69 refs., 3 figs., 4 tabs.

  11. Chromosome evolution in Neotropical butterflies.

    Science.gov (United States)

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O; Brown, Keith S

    2013-06-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results in the context of chromosome numbers of over 1400 Neotropical butterfly species and subspecies derived from about 3000 populations published here and in earlier papers of a series. The overall results show that many Neotropical groups are characterized by karyotype instability with several derived modal numbers or none at all, while almost all taxa of Lepidoptera studied from the other parts of the world have one of n = 29-31 as modal numbers. Possibly chromosome number changes become fixed in the course of speciation driven by biotic interactions. Population subdivision and structuring facilitate karyotype change. Factors that stabilize chromosome numbers include hybridization among species sharing the same number, migration, sexual selection and possibly the distribution of chromosomes within the nucleus. PMID:23865963

  12. Chromosome Architecture and Genome Organization

    Science.gov (United States)

    Bernardi, Giorgio

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few thousands Kilobases. This is a critical range that encompasses isochores, interphase chromatin domains and boundaries, and chromosomal bands. The solution rests on the following key points: 1) the transition from the looped domains and sub-domains of interphase chromatin to the 30-nm fiber loops of early prophase chromosomes goes through the unfolding into an extended chromatin structure (probably a 10-nm “beads-on-a-string” structure); 2) the architectural proteins of interphase chromatin, such as CTCF and cohesin sub-units, are retained in mitosis and are part of the discontinuous protein scaffold of mitotic chromosomes; 3) the conservation of the link between architectural proteins and their binding sites on DNA through the cell cycle explains the “mitotic memory” of interphase architecture and the reversibility of the interphase to mitosis process. The results presented here also lead to a general conclusion which concerns the existence of correlations between the isochore organization of the genome and the architecture of chromosomes from interphase to metaphase. PMID:26619076

  13. Identification of kinematic errors of five-axis machine tool trunnion axis from finished test piece

    Science.gov (United States)

    Zhang, Ya; Fu, Jianzhong; Chen, Zichen

    2014-09-01

    Compared with the traditional non-cutting measurement, machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users. However, measurement and calculation of the machining tests in the literature are quite difficult and time-consuming. A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed. Firstly, a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics. Then, the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool. By adopting the error-sensitive vectors in the matrix calculation, the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors. According to our previous work, the kinematic errors of C-axis can be treated as the known quantities, and the kinematic errors of A-axis can be obtained from the equations. This method was tested in Mikron UCP600 vertical machining center. The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis. Experimental results demonstrated that the proposed method can reduce the complexity, cost, and the time consumed substantially, and has a wider applicability. This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.

  14. Evolution of Sex Chromosomes in Insects

    OpenAIRE

    Kaiser, Vera B; Bachtrog, Doris

    2010-01-01

    Sex chromosomes have many unusual features relative to autosomes. Y (or W) chromosomes lack genetic recombination, are male- (female-) limited, and show an abundance of genetically inert heterochromatic DNA but contain few functional genes. X (or Z) chromosomes also show sex-biased transmission (i.e., X chromosomes show female-biased and Z-chromosomes show male-biased inheritance) and are hemizygous in the heterogametic sex. Their unusual ploidy level and pattern of inheritance imply that sex...

  15. Axis intersection measurement of three-axis turntable with two crosshair targets

    Institute of Scientific and Technical Information of China (English)

    REN Shun-qing; MA Guang-cheng; WANG Chang-hong

    2005-01-01

    In order to measure three-axis intersection error, two crosshair targets were fixed in the inner axis frame of a three-axis turntable. Also a theodolite was used to point its telescope to the targets and to measure the horizontal angles when three axes were on equi-spaced angle positions. The calculation equations of the axis intersection were deduced from the mounting position of the theodolite, positions of two targets, angular positions of three axes, and the measured horizontal angles with the theodolite. Finally, a practical measurement is carried out on a horizontal three-axis turntable and error analysis is conducted.

  16. Design of off-axis PIAACMC mirrors

    Science.gov (United States)

    Pluzhnik, Eugene; Guyon, Olivier; Belikov, Ruslan; Bendek, Eduardo

    2015-09-01

    The Phase-Induced Amplitude Apodization Complex Mask Coronagraph (PIAACMC) provides an efficient way to control diffraction propagation effects caused by the central obstruction/segmented mirrors of the telescope. PIAACMC can be optimized in a way that takes into account both chromatic diffraction effects caused by the telescope obstructed aperture and tip/tilt sensitivity of the coronagraph. As a result, unlike classic PIAA, the PIAACMC mirror shapes are often slightly asymmetric even for an on-axis configuration and require more care in calculating off-axis shapes when an off-axis configuration is preferred. A method to design off-axis PIAA mirror shapes given an on-axis mirror design is presented. The algorithm is based on geometrical ray tracing and is able to calculate off-axis PIAA mirror shapes for an arbitrary geometry of the input and output beams. The method is demonstrated using the third generation PIAACMC design for WFIRST-AFTA telescope. Geometrical optics design issues related to the off-axis diffraction propagation effects are also discussed.

  17. New Urban Vertical Axis Wind Turbine Design

    OpenAIRE

    Alexandru-Mihai CISMILIANU; Alexandru BOROS; Ionut-Cosmin ONCESCU; Florin FRUNZULICA

    2015-01-01

    This paper develops a different approach for enhancing the performance of Vertical Axis Wind Turbines for the use in the urban or rural environment and remote isolated residential areas. Recently the vertical axis wind turbines (VAWT) have become more attractive due to the major advantages of this type of turbines in comparison to the horizontal axis wind turbines. We aim to enhance the overall performance of the VAWT by adding a second set of blades (3 x 2=6 blades) following the rules of bi...

  18. Development of an integrated computerized scheme for metaphase chromosome image analysis: a robustness experiment

    Science.gov (United States)

    Wang, Xingwei; Zheng, Bin; Li, Shibo; Mulvihill, John J.; Wood, Marc C.; Yuan, Chaowei; Chen, Wei; Liu, Hong

    2008-02-01

    Our integrated computer-aided detection (CAD) scheme includes three basic modules. The first module detects whether a microscopic digital image depicts a metaphase chromosome cell. If a cell is detected, the scheme will justify whether it is analyzable with a decision tree. Once an analyzable cell is detected, the second module is applied to segment individual chromosomes and to compute two important features. Specifically, the scheme utilizes a modified thinning algorithm to identify the medial axis of a chromosome. By tracking perpendicular lines along the medial axis, the scheme computes four feature profiles, identifies centromeres, and assigns polarities of chromosomes based on a set of pre-optimized rules. The third module is followed to classify chromosomes into 24 types. In this module, each chromosome is initially represented by a vector of 31 features. A two-layer classifier with 8 artificial neural networks (ANN) is optimized by a genetic algorithm. A testing chromosome is first classified into one of the seven groups by the ANN in the first layer. Another ANN is then automatically selected from the seven ANNs in the second layer (one for each group) to further classify this chromosome into one of 24 types. To test the performance and robustness of this CAD scheme, we randomly selected and assembled an independent testing dataset. The dataset contains 100 microscopic digital images including 50 analyzable and 50 un-analyzable metphase cells identified by the experts. The centromere location, the corresponding polarity, and karyotype for each individual chromosome were recorded in the "truth" file. The performance of the CAD scheme applied to this image dataset is analyzed and compared with the results in the true file. The assessment accuracies are 93% for the first module, 90.8% for centromere identification and 93.2% for polarity assignment in the second module, over 96% for six chromosome groups and 81.8% for one group in the third module

  19. Myocardial reverse remodeling: how far can we rewind?

    Science.gov (United States)

    Rodrigues, Patrícia G; Leite-Moreira, Adelino F; Falcão-Pires, Inês

    2016-06-01

    Heart failure (HF) is a systemic disease that can be divided into HF with reduced ejection fraction (HFrEF) and with preserved ejection fraction (HFpEF). HFpEF accounts for over 50% of all HF patients and is typically associated with high prevalence of several comorbidities, including hypertension, diabetes mellitus, pulmonary hypertension, obesity, and atrial fibrillation. Myocardial remodeling occurs both in HFrEF and HFpEF and it involves changes in cardiac structure, myocardial composition, and myocyte deformation and multiple biochemical and molecular alterations that impact heart function and its reserve capacity. Understanding the features of myocardial remodeling has become a major objective for limiting or reversing its progression, the latter known as reverse remodeling (RR). Research on HFrEF RR process is broader and has delivered effective therapeutic strategies, which have been employed for some decades. However, the RR process in HFpEF is less clear partly due to the lack of information on HFpEF pathophysiology and to the long list of failed standard HF therapeutics strategies in these patient's outcomes. Nevertheless, new proteins, protein-protein interactions, and signaling pathways are being explored as potential new targets for HFpEF remodeling and RR. Here, we review recent translational and clinical research in HFpEF myocardial remodeling to provide an overview on the most important features of RR, comparing HFpEF with HFrEF conditions. PMID:26993225

  20. Minor groove binder distamycin remodels chromatin but inhibits transcription.

    Directory of Open Access Journals (Sweden)

    Parijat Majumder

    Full Text Available The condensed structure of chromatin limits access of cellular machinery towards template DNA. This in turn represses essential processes like transcription, replication, repair and recombination. The repression is alleviated by a variety of energy dependent processes, collectively known as "chromatin remodeling". In a eukaryotic cell, a fine balance between condensed and de-condensed states of chromatin helps to maintain an optimum level of gene expression. DNA binding small molecules have the potential to perturb such equilibrium. We present herein the study of an oligopeptide antibiotic distamycin, which binds to the minor groove of B-DNA. Chromatin mobility assays and circular dichroism spectroscopy have been employed to study the effect of distamycin on chromatosomes, isolated from the liver of Sprague-Dawley rats. Our results show that distamycin is capable of remodeling both chromatosomes and reconstituted nucleosomes, and the remodeling takes place in an ATP-independent manner. Binding of distamycin to the linker and nucleosomal DNA culminates in eviction of the linker histone and the formation of a population of off-centered nucleosomes. This hints at a possible corkscrew type motion of the DNA with respect to the histone octamer. Our results indicate that distamycin in spite of remodeling chromatin, inhibits transcription from both DNA and chromatin templates. Therefore, the DNA that is made accessible due to remodeling is either structurally incompetent for transcription, or bound distamycin poses a roadblock for the transcription machinery to advance.

  1. Role of nucleosome remodeling in neurodevelopmental and intellectual disability disorders

    Directory of Open Access Journals (Sweden)

    Alberto J Lopez

    2015-04-01

    Full Text Available It is becoming increasingly important to understand how epigenetic mechanisms control gene expression during neurodevelopment. Two epigenetic mechanisms that have received considerable attention are DNA methylation and histone acetylation. Human exome sequencing and genome-wide association studies have linked several neurobiological disorders to genes whose products actively regulate DNA methylation and histone acetylation. More recently, a third major epigenetic mechanism, nucleosome remodeling, has been implicated in human developmental and intellectual disability disorders. Nucleosome remodeling is driven primarily through nucleosome remodeling complexes with specialized ATP-dependent enzymes. These enzymes directly interact with DNA or chromatin structure, as well as histone subunits, to restructure the shape and organization of nucleosome positioning to ultimately regulate gene expression. Of particular interest is the neuron-specific Brg1/hBrm Associated Factor (nBAF complex. Mutations in nBAF subunit genes have so far been linked to Coffin-Siris syndrome, Nicolaides-Baraitser syndrome, schizophrenia, and Autism Spectrum Disorder. Together, these human developmental and intellectual disability disorders are powerful examples of the impact of epigenetic modulation on gene expression. This review focuses on the new and emerging role of nucleosome remodeling in neurodevelopmental and intellectual disability disorders and whether nucleosome remodeling affects gene expression required for cognition independently of its role in regulating gene expression required for development.

  2. Myocardial Remodeling: Cellular and Extracellular Events and Targets

    Science.gov (United States)

    Dixon, Jennifer A.; Spinale, Francis G.

    2011-01-01

    The focus of this review is on translational studies utilizing large-animal models and clinical studies that provide fundamental insight into cellular and extracellular pathways contributing to post–myocardial infarction (MI) left ventricle (LV) remodeling. Specifically, both large-animal and clinical studies have examined the potential role of endogenous and exogenous stem cells to alter the course of LV remodeling. Interestingly, there have been alterations in LV remodeling with stem cell treatment despite a lack of long-term cell engraftment. The translation of the full potential of stem cell treatments to clinical studies has yet to be realized. The modulation of proteolytic pathways that contribute to the post-MI remodeling process has also been examined. On the basis of recent large-animal studies, there appears to be a relationship between stem cell treatment post-MI and the modification of proteolytic pathways, generating the hypothesis that stem cells leave an echo effect that moderates LV remodeling. PMID:21314431

  3. Unremodeled and remodeled cardiolipin are functionally indistinguishable in yeast.

    Science.gov (United States)

    Baile, Matthew G; Sathappa, Murugappan; Lu, Ya-Wen; Pryce, Erin; Whited, Kevin; McCaffery, J Michael; Han, Xianlin; Alder, Nathan N; Claypool, Steven M

    2014-01-17

    After biosynthesis, an evolutionarily conserved acyl chain remodeling process generates a final highly homogeneous and yet tissue-specific molecular form of the mitochondrial lipid cardiolipin. Hence, cardiolipin molecules in different organisms, and even different tissues within the same organism, contain a distinct collection of attached acyl chains. This observation is the basis for the widely accepted paradigm that the acyl chain composition of cardiolipin is matched to the unique mitochondrial demands of a tissue. For this hypothesis to be correct, cardiolipin molecules with different acyl chain compositions should have distinct functional capacities, and cardiolipin that has been remodeled should promote cardiolipin-dependent mitochondrial processes better than its unremodeled form. However, functional disparities between different molecular forms of cardiolipin have never been established. Here, we interrogate this simple but crucial prediction utilizing the best available model to do so, Saccharomyces cerevisiae. Specifically, we compare the ability of unremodeled and remodeled cardiolipin, which differ markedly in their acyl chain composition, to support mitochondrial activities known to require cardiolipin. Surprisingly, defined changes in the acyl chain composition of cardiolipin do not alter either mitochondrial morphology or oxidative phosphorylation. Importantly, preventing cardiolipin remodeling initiation in yeast lacking TAZ1, an ortholog of the causative gene in Barth syndrome, ameliorates mitochondrial dysfunction. Thus, our data do not support the prevailing hypothesis that unremodeled cardiolipin is functionally distinct from remodeled cardiolipin, at least for the functions examined, suggesting alternative physiological roles for this conserved pathway. PMID:24285538

  4. Hydrogen sulfide depletion contributes to microvascular remodeling in obesity.

    Science.gov (United States)

    Candela, Joseph; Velmurugan, Gopal V; White, Carl

    2016-05-01

    Structural remodeling of the microvasculature occurs during obesity. Based on observations that impaired H2S signaling is associated with cardiovascular pathologies, the current study was designed to test the hypothesis that altered H2S homeostasis is involved in driving the remodeling process in a diet-induced mouse model of obesity. The structural and passive mechanical properties of mesenteric resistance arterioles isolated from 30-wk-old lean and obese mice were assessed using pressure myography, and vessel H2S levels were quantified using the H2S indicator sulfidefluor 7-AM. Remodeling gene expression was assessed using quantitative RT-PCR, and histological staining was used to quantify vessel collagen and elastin. Obesity was found to be associated with decreased vessel H2S concentration, inward hypertrophic remodeling, altered collagen-to-elastin ratio, and reduced vessel stiffness. In addition, mRNA levels of fibronectin, collagen types I and III, matrix metalloproteinases 2 and 9, and tissue inhibitor of metalloproteinase 1 were increased and elastin was decreased by obesity. Evidence that decreased H2S was responsible for the genetic changes was provided by experiments in which H2S levels were manipulated, either by inhibition of the H2S-generating enzyme cystathionine γ-lyase with dl-propargylglycine or by incubation with the H2S donor GYY4137. These data suggest that, during obesity, depletion of H2S is involved in orchestrating the genetic changes underpinning inward hypertrophic remodeling in the microvasculature. PMID:26993223

  5. Retrospective dosimetry using chromosome painting

    International Nuclear Information System (INIS)

    Chromosome aberration frequency measured in peripheral lymphocytes of persons exposed to ionizing radiation has been used since 1960s for dose assessment. Suspected overexposure is usually evaluated by the frequency of dicentrics and centric rings using an appropriate in vitro calibration curve. However, these chromosome aberrations are unstable with time after exposure and dose reconstruction may encounter uncertainties when the time between the exposure and the analysis is considerable or even unknown. It appears that translocations persist with time after exposure and may be used as an indication of acute past overexposures. Moreover, they appear to accumulate the cytogenetical information, which correlates with the dose received under fractionated, chronic or even occupational exposure conditions. Translocations may be detected using G-banding, which allows to score the total amount of radiation induced translocations but it is a time consuming method, or by Chromosome Painting, a method base on the Fluorescence in situ Hybridization (FISH) technique, painting only some chromosome pairs with specific whole chromosome probes and then extrapolating the observed translocation frequencies to the full genome. The latter method allows a faster aberration scoring than G-banding and appears to be the most promissory tool for biodosimetry, particularly when it is necessary to assess low doses and consequently to score a large number of metaphases, e.g. radiation workers exposed within dose limits. As with the unstable chromosome aberration, it is necessary an in vitro calibration curve based on the frequency of stable chromosome aberrations to assess doses. Our laboratory performed calibration curves for Co60 γ-rays based on the frequencies of unstable (dicentrics and centric rings detected by conventional Giemsa staining) and stable chromosome aberrations (translocations and inversions, detected by G-banding). In order to minimize the interlaboratory variability, we

  6. The Reduction of Chromosome Number in Meiosis Is Determined by Properties Built into the Chromosomes

    OpenAIRE

    Paliulis, Leocadia V.; Nicklas, R. Bruce

    2000-01-01

    In meiosis I, two chromatids move to each spindle pole. Then, in meiosis II, the two are distributed, one to each future gamete. This requires that meiosis I chromosomes attach to the spindle differently than meiosis II chromosomes and that they regulate chromosome cohesion differently. We investigated whether the information that dictates the division type of the chromosome comes from the whole cell, the spindle, or the chromosome itself. Also, we determined when chromosomes can switch from ...

  7. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  8. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/{mu}m) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  9. Dean flow fractionation of chromosomes

    Science.gov (United States)

    Hockin, Matt; Sant, Himanshu J.; Capecchi, Mario; Gale, Bruce K.

    2016-03-01

    Efforts to transfer intact mammalian chromosomes between cells have been attempted for more than 50 years with the consistent result being transfer of sub unit length pieces regardless of method. Inertial microfluidics is a new field that has shown much promise in addressing the fractionation of particles in the 2-20 μm size range (with unknown limits) and separations are based upon particles being carried by curving confined flows (within a spiral shaped, often rectangular flow chamber) and migrating to stable "equilibrium" positions of varying distance from a chamber wall depending on the balance of dean and lift forces. We fabricated spiral channels for inertial microfluidic separations using a standard soft lithography process. The concentration of chromosomes, small contaminant DNA and large cell debris in each outlets were evaluated using microscope (60X) and a flow cytometer. Using Dean Flow Fractionation, we were able to focus 4.5 times more chromosomes in outlet 2 compared to outlet 4 where most of the large debris is found. We recover 16% of the chromosomes in outlet #1- 50% in 2, 23% in 3 and 11% in 4. It should be noted that these estimates of recovery do not capture one piece of information- it actually may be that the chromosomes at each outlet are physically different and work needs to be done to verify this potential.

  10. Plasma stabilization in traps with spatial axis

    International Nuclear Information System (INIS)

    Possible methods of plasma stabilization within traps with spatial axis for both circular and triangular-elliptic magnetic surfaces, applicable to Dracon, Spitzer's Eight and Heliac, are studied theoretically. (author). 18 refs, 5 figs

  11. Axis of Zodiacal light Near Tropic Cancer

    CERN Document Server

    Nawar, S; Mikhail, J S; Morcos, A B; Ibrahim, Alhassan I

    2014-01-01

    The axis of zodiacal lights have been obtained in blue and yellow colors using photoelectric observations of zodiacal light. These observations have been carried out at Abu Simbel Site in Egypt, in October 1975. This site lies too near to the tropic of Cancer, at which the axis of the zodiacal light cone perpendiculars to the horizon. The results show that the plane of the zodiacal light is inclined to the normal by 1.59 degrees in blue color and 1.18 degrees in yellow color. This means that there is a slight variation in zodiacal light axis with wavelength, and the axis almost coincide with the ecliptic. The present results for blue color can be considered as the first one in the world near the tropic of Cancer.

  12. Chromosomal rearrangement interferes with meiotic X chromosome inactivation

    Czech Academy of Sciences Publication Activity Database

    Homolka, David; Ivánek, Robert; Čapková, Jana; Jansa, Petr; Forejt, Jiří

    2007-01-01

    Roč. 17, č. 10 (2007), s. 1431-1437. ISSN 1088-9051 R&D Projects: GA MŠk(CZ) 1M0520; GA ČR GA301/06/1334; GA ČR GA301/07/1383 Grant ostatní: Howard Hughes Medical Institute(US) HHMI 55000306 Institutional research plan: CEZ:AV0Z50520514 Keywords : chromosomal translocations * meiotic X chromosome inactivation * spermatogenesis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 11.224, year: 2007

  13. Uptake and remodeling of exogenous phosphatidylethanolamine in E. coli.

    Science.gov (United States)

    Kol, Matthijs A; Kuster, Diederik W D; Boumann, Henry A; de Cock, Hans; Heck, Albert J R; de Kruijff, Ben; de Kroon, Anton I P M

    2004-03-22

    The fate of exogenous short-chain analogues of phosphatidylethanolamine and phosphatidylserine was studied in a deep-rough derivative of E. coli mutant strain AD93 that cannot synthesize phosphatidylethanolamine de novo. Using mass spectrometry, it was shown that dicaproyl(di 6:0)-phosphatidylethanolamine is extensively remodeled, eventually adopting the phosphatidylethanolamine species profile of the parental wild-type strain of AD93. Dicaproyl-phosphatidylserine was decarboxylated to form phosphatidylethanolamine, and yielded a species profile, which strongly resembled that of the introduced phosphatidylethanolamine. This demonstrates transport of phosphatidylserine to the cytosolic leaflet of the inner membrane. The changes of the species profile of phosphatidylethanolamine indicate that the short-chain phospholipids are most likely remodeled via two consecutive acyl chain substitutions, and at least part of this remodeling involves transport to the inner membrane. PMID:15164768

  14. UMAPRM: Uniformly sampling the medial axis

    KAUST Repository

    Yeh, Hsin-Yi Cindy

    2014-05-01

    © 2014 IEEE. Maintaining clearance, or distance from obstacles, is a vital component of successful motion planning algorithms. Maintaining high clearance often creates safer paths for robots. Contemporary sampling-based planning algorithms That utilize The medial axis, or The set of all points equidistant To Two or more obstacles, produce higher clearance paths. However, They are biased heavily Toward certain portions of The medial axis, sometimes ignoring parts critical To planning, e.g., specific Types of narrow passages. We introduce Uniform Medial Axis Probabilistic RoadMap (UMAPRM), a novel planning variant That generates samples uniformly on The medial axis of The free portion of Cspace. We Theoretically analyze The distribution generated by UMAPRM and show its uniformity. Our results show That UMAPRM\\'s distribution of samples along The medial axis is not only uniform but also preferable To other medial axis samplers in certain planning problems. We demonstrate That UMAPRM has negligible computational overhead over other sampling Techniques and can solve problems The others could not, e.g., a bug Trap. Finally, we demonstrate UMAPRM successfully generates higher clearance paths in The examples.

  15. Parallel mechanisms suppress cochlear bone remodeling to protect hearing.

    Science.gov (United States)

    Jáuregui, Emmanuel J; Akil, Omar; Acevedo, Claire; Hall-Glenn, Faith; Tsai, Betty S; Bale, Hrishikesh A; Liebenberg, Ellen; Humphrey, Mary Beth; Ritchie, Robert O; Lustig, Lawrence R; Alliston, Tamara

    2016-08-01

    Bone remodeling, a combination of bone resorption and formation, requires precise regulation of cellular and molecular signaling to maintain proper bone quality. Whereas osteoblasts deposit and osteoclasts resorb bone matrix, osteocytes both dynamically resorb and replace perilacunar bone matrix. Osteocytes secrete proteases like matrix metalloproteinase-13 (MMP13) to maintain the material quality of bone matrix through perilacunar remodeling (PLR). Deregulated bone remodeling impairs bone quality and can compromise hearing since the auditory transduction mechanism is within bone. Understanding the mechanisms regulating cochlear bone provides unique ways to assess bone quality independent of other aspects that contribute to bone mechanical behavior. Cochlear bone is singular in its regulation of remodeling by expressing high levels of osteoprotegerin. Since cochlear bone expresses a key PLR enzyme, MMP13, we examined whether cochlear bone relies on, or is protected from, osteocyte-mediated PLR to maintain hearing and bone quality using a mouse model lacking MMP13 (MMP13(-/-)). We investigated the canalicular network, collagen organization, lacunar volume via micro-computed tomography, and dynamic histomorphometry. Despite finding defects in these hallmarks of PLR in MMP13(-/-) long bones, cochlear bone revealed no differences in these markers, nor hearing loss as measured by auditory brainstem response (ABR) or distortion product oto-acoustic emissions (DPOAEs), between wild type and MMP13(-/-) mice. Dynamic histomorphometry revealed abundant PLR by tibial osteocytes, but near absence in cochlear bone. Cochlear suppression of PLR corresponds to repression of several key PLR genes in the cochlea relative to long bones. These data suggest that cochlear bone uniquely maintains bone quality and hearing independent of MMP13-mediated osteocytic PLR. Furthermore, the cochlea employs parallel mechanisms to inhibit remodeling by osteoclasts and osteoblasts, and by

  16. Chromatin remodeling occurs independent of transcription factor binding during 5-azacytidine reactivation of the human HPRT gene

    Energy Technology Data Exchange (ETDEWEB)

    Hornstra, L.K.; Litt, M.D.; Yang, T.P. [Univ. of Florida College of Medicine, Gainesville, FL (United States)] [and others

    1994-09-01

    A novel system of differential gene expression in mammals is established during normal female embryogenesis by X chromosome inactivation. Studies of 5-aza-2{prime}-deoxycytidine (5aCdr)-induced reactivation of genes on the inactive human X chromosome strongly implicate DNA methylation in maintaining the transcriptional repression of discrete loci on the inactive X. During the process of 5aCdr-induced reactivation of the human hypoxanthine phosphoribosyltransferase (HPRT) gene on the inactive X chromosome, changes in nuclease sensitivity of chromatin in the 5{prime} region of the HPRT gene and HPRT mRNA levels have been analyzed from 0-72 hrs. after 5aCdr exposure. Increased nuclease sensitivity is first detectable at 6 hrs. and reaches a maximum at 24 hrs. after initial exposure to 5aCdr, while the appearance of HPRT mRNA levels is first detectable by RT-PCR at 24 hrs. and reaches a maximum of 48 hrs. after 5aCdr exposure. Thus, the change in chromatin structure of the 5{prime} region as a result of 5aCdr treatment appears to occur prior to active transcription of the gene. However, it is unclear if the remodeling of chromatin requires the binding of transcription factors to the 5{prime} region, or if the binding of transcription factors is only required for transcription of the HPRT gene. We now have assayed the binding of transcription factors to the 5{prime} region of the HPRT gene on the inactive X chromosome during 5aCdr reactivation. We find that the change in chromatin structure as a result of 5aCdr treatment occurs independent of transcription factor binding, and that the binding of factors is correlated with active transcription of the gene rather than remodeling of chromatin structure. These data suggest that the differential binding of transcriptional activators (and differential expression of the HPRT gene) to the active and inactive HPRT genes is modulated by the accessibility of their binding sites due to chromatin structure.

  17. Escape Artists of the X Chromosome.

    Science.gov (United States)

    Balaton, Bradley P; Brown, Carolyn J

    2016-06-01

    Inactivation of one X chromosome in mammalian females achieves dosage compensation between XX females and XY males; however, over 15% of human X-linked genes continue to be expressed from the inactive X chromosome. New genomic methodologies have improved our identification and characterization of these escape genes, revealing the importance of DNA sequence, chromatin structure, and chromosome ultrastructure in regulating expression from an otherwise inactive chromosome. Study of these exceptions to the rule of silencing highlights the interconnectedness of chromatin and chromosome structure in X-chromosome inactivation (XCI). Recent advances also demonstrate the importance of these genes in sexually dimorphic disease risk, particularly cancer. PMID:27103486

  18. Silent Synapse-Based Circuitry Remodeling in Drug Addiction.

    Science.gov (United States)

    Dong, Yan

    2016-05-01

    Exposure to cocaine, and likely other drugs of abuse, generates α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-silent glutamatergic synapses in the nucleus accumbens. These immature synaptic contacts evolve after drug withdrawal to redefine the neurocircuital properties. These results raise at least three critical questions: (1) what are the molecular and cellular mechanisms that mediate drug-induced generation of silent synapses; (2) how are neurocircuits remodeled upon generation and evolution of drug-generated silent synapses; and (3) what behavioral consequences are produced by silent synapse-based circuitry remodeling? This short review analyzes related experimental results, and extends them to some speculations. PMID:26721952

  19. Efficient computational simulation of actin stress fiber remodeling.

    Science.gov (United States)

    Ristori, T; Obbink-Huizer, C; Oomens, C W J; Baaijens, F P T; Loerakker, S

    2016-09-01

    Understanding collagen and stress fiber remodeling is essential for the development of engineered tissues with good functionality. These processes are complex, highly interrelated, and occur over different time scales. As a result, excessive computational costs are required to computationally predict the final organization of these fibers in response to dynamic mechanical conditions. In this study, an analytical approximation of a stress fiber remodeling evolution law was derived. A comparison of the developed technique with the direct numerical integration of the evolution law showed relatively small differences in results, and the proposed method is one to two orders of magnitude faster. PMID:26823159

  20. Adults with Chromosome 18 Abnormalities.

    Science.gov (United States)

    Soileau, Bridgette; Hasi, Minire; Sebold, Courtney; Hill, Annice; O'Donnell, Louise; Hale, Daniel E; Cody, Jannine D

    2015-08-01

    The identification of an underlying chromosome abnormality frequently marks the endpoint of a diagnostic odyssey. However, families are frequently left with more questions than answers as they consider their child's future. In the case of rare chromosome conditions, a lack of longitudinal data often makes it difficult to provide anticipatory guidance to these families. The objective of this study is to describe the lifespan, educational attainment, living situation, and behavioral phenotype of adults with chromosome 18 abnormalities. The Chromosome 18 Clinical Research Center has enrolled 483 individuals with one of the following conditions: 18q-, 18p-, Tetrasomy 18p, and Ring 18. As a part of the ongoing longitudinal study, we collect data on living arrangements, educational level attained, and employment status as well as data on executive functioning and behavioral skills on an annual basis. Within our cohort, 28 of the 483 participants have died, the majority of whom have deletions encompassing the TCF4 gene or who have unbalanced rearrangement involving other chromosomes. Data regarding the cause of and age at death are presented. We also report on the living situation, educational attainment, and behavioral phenotype of the 151 participants over the age of 18. In general, educational level is higher for people with all these conditions than implied by the early literature, including some that received post-high school education. In addition, some individuals are able to live independently, though at this point they represent a minority of patients. Data on executive function and behavioral phenotype are also presented. Taken together, these data provide insight into the long-term outcome for individuals with a chromosome 18 condition. This information is critical in counseling families on the range of potential outcomes for their child. PMID:25403900

  1. Making chromosome abnormalities treatable conditions.

    Science.gov (United States)

    Cody, Jannine DeMars; Hale, Daniel Esten

    2015-09-01

    Individuals affected by the classic chromosome deletion syndromes which were first identified at the beginning of the genetic age, are now positioned to benefit from genomic advances. This issue highlights five of these conditions (4p-, 5p-, 11q-, 18p-, and 18q-). It focuses on the increased in understanding of the molecular underpinnings and envisions how these can be transformed into effective treatments. While it is scientifically exciting to see the phenotypic manifestations of hemizygosity being increasingly understood at the molecular and cellular level, it is even more amazing to consider that we are now on the road to making chromosome abnormalities treatable conditions. PMID:26351122

  2. Using Chromosomes to Teach Evolution: Chromosomal Rearrangements in Speciation Events.

    Science.gov (United States)

    Offner, Susan

    1994-01-01

    Uses diagrams to aid in discussing how the English map of the human chromosomes, published by Offner in 1993, can be used to illustrate some important questions in evolution, as well as give students a glimpse into some of the mechanisms underlying evolutionary change. (ZWH)

  3. Gene by Environment Interaction Linking the Chromosome 15q25 Locus With Cigarette Consumption and Lung Cancer Susceptibility — Are African American Affected Differently?

    OpenAIRE

    Hopkins, R.J.; R. P. Young

    2016-01-01

    The majority of lung cancer cases result from complex interactions between smoking exposure, genetic susceptibility and a person's immune response to chronic inflammation or lung remodelling. Epidemiological studies confirm that susceptibility to developing chronic obstructive pulmonary disease (COPD), especially emphysema, is also closely linked to lung cancer susceptibility. Genetic epidemiology studies have consistently reported associations between the chromosome 15q25 locus with lung can...

  4. Actuator assembly including a single axis of rotation locking member

    Science.gov (United States)

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  5. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; MATSHUDA, Yoichi; 秀之, 田辺

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7–10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  6. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; Matsuda, Yoichi

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7Y10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  7. Mathematical glimpse on the Y chromosome degeneration

    Science.gov (United States)

    Lobo, M. P.

    2006-04-01

    The Y chromosomes are genetically degenerate and do not recombine with their matching partners X. Non-recombination of XY pairs has been pointed out as the key factor for the degeneration of the Y chromosome. The aim here is to show that there is a mathematical asymmetry in sex chromosomes which leads to the degeneration of Y chromosomes even in the absence of XX and XY recombination. A model for sex-chromosome evolution in a stationary regime is proposed. The consequences of their asymmetry are analyzed and lead us to a couple of conclusions. First, Y chromosome degeneration shows up sqrt{2} more often than X chromosome degeneration. Second, if nature prohibits female mortalities from beeing exactly 50%, then Y chromosome degeneration is inevitable.

  8. CHROMOSOMAL MULTIPLICITY IN BURKHOLDERIA CEPACIA

    Science.gov (United States)

    We have used CHEF gel electrophoresis to screen preparations of large DNA from different Burkholderia cepacia isolates for the presence of DNA species corresponding to the linearized forms of the three chromosomes of 3.4,2.5, and 0.9 Mb identified in B. cepacia strain 17616. DNA ...

  9. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished...

  10. Chromosome Territory Modeller and Viewer.

    Science.gov (United States)

    Tkacz, Magdalena A; Chromiński, Kornel; Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi-a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license. PMID:27505434

  11. Chromosome Territory Modeller and Viewer

    Science.gov (United States)

    Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi–a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license. PMID:27505434

  12. The CHD remodeling factor Hrp1 stimulates CENP-A loading to centromeres.

    Science.gov (United States)

    Walfridsson, Julian; Bjerling, Pernilla; Thalen, Maria; Yoo, Eung-Jae; Park, Sang Dai; Ekwall, Karl

    2005-01-01

    Centromeres of fission yeast are arranged with a central core DNA sequence flanked by repeated sequences. The centromere-associated histone H3 variant Cnp1 (SpCENP-A) binds exclusively to central core DNA, while the heterochromatin proteins and cohesins bind the surrounding outer repeats. CHD (chromo-helicase/ATPase DNA binding) chromatin remodeling factors were recently shown to affect chromatin assembly in vitro. Here, we report that the CHD protein Hrp1 plays a key role at fission yeast centromeres. The hrp1Delta mutant disrupts silencing of the outer repeats and central core regions of the centromere and displays chromosome segregation defects characteristic for dysfunction of both regions. Importantly, Hrp1 is required to maintain high levels of Cnp1 and low levels of histone H3 and H4 acetylation at the central core region. Hrp1 interacts directly with the centromere in early S-phase when centromeres are replicated, suggesting that Hrp1 plays a direct role in chromatin assembly during DNA replication. PMID:15908586

  13. Can experimental data in humans verify the finite element-based bone remodeling algorithm?

    DEFF Research Database (Denmark)

    Wong, Christian; Gehrchen, P Martin; Kiaer, Thomas

    2008-01-01

    A finite element analysis-based bone remodeling study in human was conducted in the lumbar spine operated on with pedicle screws. Bone remodeling results were compared to prospective experimental bone mineral content data of patients operated on with pedicle screws.......A finite element analysis-based bone remodeling study in human was conducted in the lumbar spine operated on with pedicle screws. Bone remodeling results were compared to prospective experimental bone mineral content data of patients operated on with pedicle screws....

  14. Cerebral Salt Wasting Syndrome After Calvarial Remodeling in Craniosynostosis

    OpenAIRE

    Byeon, Jun-Hee; Yoo, Gyeol

    2005-01-01

    Hyponatremia and increased urine output after calvarial remodeling have been noted in pediatric patients with craniosynostosis. If not treated properly, patients develop hypoosmotic conditions that can lead to cerebral edema, increased intracranial pressure, and collapsed circulation. Postoperative hyponatremia after central nervous system surgery is considered as the syndrome of inappropriate antidiuretic hormone (SIADH) secretion. Recently, however, cerebral salt wasting syndrome (CSWS) ins...

  15. The redox state of transglutaminase 2 controls arterial remodeling

    DEFF Research Database (Denmark)

    van den Akker, Jeroen; VanBavel, Ed; van Geel, Remon;

    2011-01-01

    While inward remodeling of small arteries in response to low blood flow, hypertension, and chronic vasoconstriction depends on type 2 transglutaminase (TG2), the mechanisms of action have remained unresolved. We studied the regulation of TG2 activity, its (sub) cellular localization, substrates, ...

  16. Role of nucleosome remodeling in neurodevelopmental and intellectual disability disorders

    OpenAIRE

    Lopez, Alberto J.; Wood, Marcelo A.

    2015-01-01

    It is becoming increasingly important to understand how epigenetic mechanisms control gene expression during neurodevelopment. Two epigenetic mechanisms that have received considerable attention are DNA methylation and histone acetylation. Human exome sequencing and genome-wide association studies have linked several neurobiological disorders to genes whose products actively regulate DNA methylation and histone acetylation. More recently, a third major epigenetic mechanism, nucleosome remodel...

  17. CREB Selectively Controls Learning-Induced Structural Remodeling of Neurons

    Science.gov (United States)

    Middei, Silvia; Spalloni, Alida; Longone, Patrizia; Pittenger, Christopher; O'Mara, Shane M.; Marie, Helene; Ammassari-Teule, Martine

    2012-01-01

    The modulation of synaptic strength associated with learning is post-synaptically regulated by changes in density and shape of dendritic spines. The transcription factor CREB (cAMP response element binding protein) is required for memory formation and in vitro dendritic spine rearrangements, but its role in learning-induced remodeling of neurons…

  18. Pentoxifylline Attenuates Cardiac Remodeling Induced by Tobacco Smoke Exposure

    Directory of Open Access Journals (Sweden)

    Marcos Minicucci

    2016-01-01

    Full Text Available Abstract Background: Tobacco smoke exposure is an important risk factor for cardiac remodeling. Under this condition, inflammation, oxidative stress, energy metabolism abnormalities, apoptosis, and hypertrophy are present. Pentoxifylline has anti‑inflammatory, anti-apoptotic, anti-thrombotic and anti-proliferative properties. Objective: The present study tested the hypothesis that pentoxifylline would attenuate cardiac remodeling induced by smoking. Methods: Wistar rats were distributed in four groups: Control (C, Pentoxifylline (PX, Tobacco Smoke (TS, and PX-TS. After two months, echocardiography, invasive blood pressure measurement, biochemical, and histological studies were performed. The groups were compared by two-way ANOVA with a significance level of 5%. Results: TS increased left atrium diameter and area, which was attenuated by PX. In the isolated heart study, TS lowered the positive derivate (+dp/dt, and this was attenuated by PX. The antioxidants enzyme superoxide dismutase and glutathione peroxidase were decreased in the TS group; PX recovered these activities. TS increased lactate dehydrogenase (LDH and decreased 3-hydroxyacyl Coenzyme A dehydrogenases (OH-DHA and citrate synthase (CS. PX attenuated LDH, 3-OH-DHA and CS alterations in TS-PX group. TS increased IL-10, ICAM-1, and caspase-3. PX did not influence these variables. Conclusion: TS induced cardiac remodeling, associated with increased inflammation, oxidative stress, apoptosis, and changed energy metabolism. PX attenuated cardiac remodeling by reducing oxidative stress and improving cardiac bioenergetics, but did not act upon cardiac cytokines and apoptosis.

  19. Remodeling in asthma and chronic obstructive pulmonary disease

    NARCIS (Netherlands)

    Postma, Dirkje S; Timens, Wim

    2006-01-01

    Airway and lung tissue remodeling and fibrosis play an important role in the development of symptoms associated with lung function loss in asthma and chronic obstructive pulmonary disease (COPD). In the past decades, much attention has been paid to the inflammatory cellular process involved in airwa

  20. Remodeling of inhibitory synaptic connections in developing ferret visual cortex

    Directory of Open Access Journals (Sweden)

    Dalva Matthew B

    2010-02-01

    Full Text Available Abstract Background In the visual cortex, as in many other regions of the developing brain, excitatory synaptic connections undergo substantial remodeling during development. While evidence suggests that local inhibitory synapses may behave similarly, the extent and mechanisms that mediate remodeling of inhibitory connections are not well understood. Results Using scanning laser photostimulation in slices of developing ferret visual cortex, we assessed the overall patterns of developing inhibitory and excitatory synaptic connections converging onto individual neurons. Inhibitory synaptic inputs onto pyramidal neurons in cortical layers 2 and 3 were already present as early as postnatal day 20, well before eye opening, and originated from regions close to the recorded neurons. During the ensuing 2 weeks, the numbers of synaptic inputs increased, with the numbers of inhibitory (and excitatory synaptic inputs peaking near the time of eye opening. The pattern of inhibitory inputs refined rapidly prior to the refinement of excitatory inputs. By uncaging the neurotransmtter GABA in brain slices from animals of different ages, we find that this rapid refinement correlated with a loss of excitatory activity by GABA. Conclusion Inhibitory synapses, like excitatory synapses, undergo significant postnatal remodeling. The time course of the remodeling of inhibitory connections correlates with the emergence of orientation tuning in the visual cortex, implicating these rearrangements in the genesis of adult cortical response properties.

  1. Multiphase modeling of tumor growth with matrix remodeling and fibrosis

    CERN Document Server

    Tosin, Andrea

    2009-01-01

    We present a multiphase mathematical model for tumor growth which incorporates the remodeling of the extracellular matrix and describes the formation of fibrotic tissue by tumor cells. We also detail a full qualitative analysis of the spatially homogeneous problem, and study the equilibria of the system in order to characterize the conditions under which fibrosis may occur.

  2. Molecular Mechanisms of Pulmonary Vascular Remodeling in Pulmonary Arterial Hypertension

    Science.gov (United States)

    Leopold, Jane A.; Maron, Bradley A.

    2016-01-01

    Pulmonary arterial hypertension (PAH) is a devastating disease that is precipitated by hypertrophic pulmonary vascular remodeling of distal arterioles to increase pulmonary artery pressure and pulmonary vascular resistance in the absence of left heart, lung parenchymal, or thromboembolic disease. Despite available medical therapy, pulmonary artery remodeling and its attendant hemodynamic consequences result in right ventricular dysfunction, failure, and early death. To limit morbidity and mortality, attention has focused on identifying the cellular and molecular mechanisms underlying aberrant pulmonary artery remodeling to identify pathways for intervention. While there is a well-recognized heritable genetic component to PAH, there is also evidence of other genetic perturbations, including pulmonary vascular cell DNA damage, activation of the DNA damage response, and variations in microRNA expression. These findings likely contribute, in part, to dysregulation of proliferation and apoptosis signaling pathways akin to what is observed in cancer; changes in cellular metabolism, metabolic flux, and mitochondrial function; and endothelial-to-mesenchymal transition as key signaling pathways that promote pulmonary vascular remodeling. This review will highlight recent advances in the field with an emphasis on the aforementioned molecular mechanisms as contributors to the pulmonary vascular disease pathophenotype. PMID:27213345

  3. Lessons from Anaplasma phagocytophilum: Chromatin Remodeling by Bacterial Effectors

    OpenAIRE

    Rennoll-Bankert, Kristen E.; Dumler, J. Stephen

    2012-01-01

    Bacterial pathogens can alter global host gene expression via histone modifications and chromatin remodeling in order to subvert host responses, including those involved with innate immunity, allowing for bacterial survival. Shigella flexneri, Listeria monocytogenes, Chlamydia trachomatis, and Anaplasma phagocytophilum express effector proteins that modify host histones and chromatin structure. A. phagocytophilum modulates granulocyte respiratory burst in part by dampening transcription of se...

  4. School Buildings: Remodeling; Rehabilitation; Modernization; Repair. Bulletin, 1950, No. 17

    Science.gov (United States)

    Yiles, Nelson E.

    1950-01-01

    Adequate school plants are essential to a modern educational program. The school plant that is not properly maintained soon fails to provide the service for which it was intended. The total program of maintenance, including repairs, renovation, remodeling, rehabilitation, and modernization should be carefully planned. Some tasks will recur at…

  5. Chromatin remodelers in the DNA double strand break response

    NARCIS (Netherlands)

    Smeenk, Godelieve

    2012-01-01

    During my PhD project, I studied the role of several chromatin remodelers in the DNA double strand break (DSB) response. We discovered that both CHD4 and SMARCA5 are required for ubiquitin signaling through the E3 ubiquitin ligases RNF8 and RNF168, which is a central signaling event in the response

  6. "New Professionalism," Workforce Remodeling and the Restructuring of Teachers' Work

    Science.gov (United States)

    Stevenson, Howard; Carter, Bob; Passy, Rowena

    2007-01-01

    Since its election in 1997 the Labour government's policy has sought to promote a "new professionalism" amongst teachers. First mooted at the time when new performance management arrangements were introduced, the discourse of new professionalism has now become closely associated with the "workforce remodeling" agenda in which teachers' work is…

  7. Artery Remodeling Under Axial Twist in Three Days Organ Culture.

    Science.gov (United States)

    Wang, Guo-Liang; Xiao, Yangming; Voorhees, Andrew; Qi, Ying-Xin; Jiang, Zong-Lai; Han, Hai-Chao

    2015-08-01

    Arteries often endure axial twist due to body movement and surgical procedures, but how arteries remodel under axial twist remains unclear. The objective of this study was to investigate early stage arterial wall remodeling under axial twist. Porcine carotid arteries were twisted axially and maintained for three days in ex vivo organ culture systems while the pressure and flow remained the same as untwisted controls. Cell proliferation, internal elastic lamina (IEL) fenestrae shape and size, endothelial cell (EC) morphology and orientation, as well as the expression of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, and tissue inhibitor of metalloproteinase-2 (TIMP-2) were quantified using immunohistochemistry staining and immunoblotting. Our results demonstrated that cell proliferation in both the intima and media were significantly higher in the twisted arteries compared to the controls. The cell proliferation in the intima increased from 1.33 ± 0.21% to 7.63 ± 1.89%, and in the media from 1.93 ± 0.84% to 8.27 ± 2.92% (p culture, a decrease from the initial 15.58 ± 1.29 degrees. These results demonstrate that axial twist can stimulate artery remodeling. These findings complement our understanding of arterial wall remodeling under mechanical stress resulting from pressure and flow variations. PMID:25503524

  8. Energy Efficiency Measures to Incorporate into Remodeling Projects

    Energy Technology Data Exchange (ETDEWEB)

    Liaukus, C. [Building America Research Alliance, Kent, WA (United States)

    2014-12-01

    Energy improvements in a home are often approached as one concerted effort, beginning with a simple walk-through assessment or more in-depth energy audit and followed by the installation of recommended energy measures. While this approach allows for systems thinking to guide the efforts, comprehensive energy improvements of this nature are undertaken by a relatively small number of U.S. households compared to piecemeal remodeling efforts. In this report, the U.S Department of Energy Building America Retrofit Alliance research team examines the improvement of a home’s energy performance in an opportunistic way by examining what can be done to incorporate energy efficiency measures into general remodeling work and home repair projects. This allows for energy efficiency upgrades to occur at the same time as remodeling proejcts. There are challenges to this approach, not the least of which being that the work will take place over time in potentially many separate projects. The opportunity to improve a home’s energy efficiency at one time expands or contracts with the scope of the remodel. As such, guidance on how to do each piece thoughtfully and with consideration for potential future projects, is critical.

  9. Lung tissue remodeling in the acute respiratory distress syndrome

    Directory of Open Access Journals (Sweden)

    Souza Alba Barros de

    2003-01-01

    Full Text Available Acute respiratory distress syndrome (ARDS is characterized by diffuse alveolar damage, and evolves progressively with three phases: exsudative, fibroproliferative, and fibrotic. In the exudative phase, there are interstitial and alveolar edemas with hyaline membrane. The fibropro­liferative phase is characterized by exudate organization and fibroelastogenesis. There is proliferation of type II pneumocytes to cover the damaged epithelial surface, followed by differentiation into type I pneumocytes. The fibroproliferative phase starts early, and its severity is related to the patient?s prognosis. The alterations observed in the phenotype of the pulmonary parenchyma cells steer the tissue remodeling towards either progressive fibrosis or the restoration of normal alveolar architecture. The fibrotic phase is characterized by abnormal and excessive deposition of extracellular matrix proteins, mainly collagen. The dynamic control of collagen deposition and degradation is regulated by metalloproteinases and their tissular regulators. The deposition of proteoglycans in the extracellular matrix of ARDS patients needs better study. The regulation of extracellular matrix remodeling, in normal conditions or in several pulmonary diseases, such as ARDS, results from a complex mechanism that integrate the transcription of elements that destroy the matrix protein and produce activation/inhibition of several cellular types of lung tissue. This review article will analyze the ECM organization in ARDS, the different pulmonary parenchyma remodeling mechanisms, and the role of cytokines in the regulation of the different matrix components during the remodeling process.

  10. Molecular Mechanisms of Pulmonary Vascular Remodeling in Pulmonary Arterial Hypertension

    Directory of Open Access Journals (Sweden)

    Jane A. Leopold

    2016-05-01

    Full Text Available Pulmonary arterial hypertension (PAH is a devastating disease that is precipitated by hypertrophic pulmonary vascular remodeling of distal arterioles to increase pulmonary artery pressure and pulmonary vascular resistance in the absence of left heart, lung parenchymal, or thromboembolic disease. Despite available medical therapy, pulmonary artery remodeling and its attendant hemodynamic consequences result in right ventricular dysfunction, failure, and early death. To limit morbidity and mortality, attention has focused on identifying the cellular and molecular mechanisms underlying aberrant pulmonary artery remodeling to identify pathways for intervention. While there is a well-recognized heritable genetic component to PAH, there is also evidence of other genetic perturbations, including pulmonary vascular cell DNA damage, activation of the DNA damage response, and variations in microRNA expression. These findings likely contribute, in part, to dysregulation of proliferation and apoptosis signaling pathways akin to what is observed in cancer; changes in cellular metabolism, metabolic flux, and mitochondrial function; and endothelial-to-mesenchymal transition as key signaling pathways that promote pulmonary vascular remodeling. This review will highlight recent advances in the field with an emphasis on the aforementioned molecular mechanisms as contributors to the pulmonary vascular disease pathophenotype.

  11. Fronto-Orbital Advancement and Total Calvarial Remodelling for Craniosynostosis

    International Nuclear Information System (INIS)

    Objective: To describe the results of fronto-orbital advancement and remodelling for craniosynostosis in children. Study Design: Case series. Place and Duration of Study: Department of Plastic Surgery, Combined Military Hospital, Rawalpindi, from June 2009 to June 2012. Methodology: All the patients with cranial suture synostosis operated were included in the study. Those patients who were lost to follow-up were excluded. Variables considered were age, gender, type of synostosis, intracranial pressure, and history of previous surgeries for the same problem. Outcome measures were studied in terms of improvement of skull measurements (anteroposterior and bicoronal), duration of surgery, hospital stay, blood transfusions, complications and parents satisfaction. Results: A total of 36 patients were included in the study. Male to female ratio was 3:1. The age ranged from 5 to 54 months. Thirty two patients presented with non-syndromic and four with syndromic craniosynostosis. Fronto orbital advancement and total calvarial remodelling was done in 26 and 10 patients respectively. There was improvement in the skull measurements and the parents were satisfied in all cases with the skull shape. Complications occurred in 11.1% including chest and wound infection and one death. Conclusion: Fronto-orbital advancement and remodelling is an effective procedure for the correction of craniosynostosis, however, individual cases may require other procedures like total calvarial remodelling. (author)

  12. Multicolor spectral karyotyping of human chromosomes.

    Science.gov (United States)

    Schröck, E; du Manoir, S; Veldman, T; Schoell, B; Wienberg, J; Ferguson-Smith, M A; Ning, Y; Ledbetter, D H; Bar-Am, I; Soenksen, D; Garini, Y; Ried, T

    1996-07-26

    The simultaneous and unequivocal discernment of all human chromosomes in different colors would be of significant clinical and biologic importance. Whole-genome scanning by spectral karyotyping allowed instantaneous visualization of defined emission spectra for each human chromosome after fluorescence in situ hybridization. By means of computer separation (classification) of spectra, spectrally overlapping chromosome-specific DNA probes could be resolved, and all human chromosomes were simultaneously identified. PMID:8662537

  13. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH SPERM DISORDERS

    OpenAIRE

    L. Y. Pylyp; L. A. Spinenko; V. D. Zukin; N. M. Bilko

    2013-01-01

    Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intrac...

  14. Evolution of sex chromosomes ZW of Schistosoma mansoni inferred from chromosome paint and BAC mapping analyses.

    Science.gov (United States)

    Hirai, Hirohisa; Hirai, Yuriko; LoVerde, Philip T

    2012-12-01

    Chromosomes of schistosome parasites among digenetic flukes have a unique evolution because they exhibit the sex chromosomes ZW, which are not found in the other groups of flukes that are hermaphrodites. We conducted molecular cytogenetic analyses for investigating the sex chromosome evolution using chromosome paint analysis and BAC clones mapping. To carry this out, we developed a technique for making paint probes of genomic DNA from a single scraped chromosome segment using a chromosome microdissection system, and a FISH mapping technique for BAC clones. Paint probes clearly identified each of the 8 pairs of chromosomes by a different fluorochrome color. Combination analysis of chromosome paint analysis with Z/W probes and chromosome mapping with 93 BAC clones revealed that the W chromosome of Schistosoma mansoni has evolved by at least four inversion events and heterochromatinization. Nine of 93 BAC clones hybridized with both the Z and W chromosomes, but the locations were different between Z and W chromosomes. The homologous regions were estimated to have moved from the original Z chromosome to the differentiated W chromosome by three inversions events that occurred before W heterohcromatinization. An inversion that was observed in the heterochromatic region of the W chromosome likely occurred after W heterochromatinization. These inversions and heterochromatinization are hypothesized to be the key factors that promoted the evolution of the W chromosome of S. mansoni. PMID:22831897

  15. HTLV-1 Tax mediated downregulation of miRNAs associated with chromatin remodeling factors in T cells with stably integrated viral promoter.

    Directory of Open Access Journals (Sweden)

    Saifur Rahman

    Full Text Available RNA interference (RNAi is a natural cellular mechanism to silence gene expression and is predominantly mediated by microRNAs (miRNAs that target messenger RNA. Viruses can manipulate the cellular processes necessary for their replication by targeting the host RNAi machinery. This study explores the effect of human T-cell leukemia virus type 1 (HTLV-1 transactivating protein Tax on the RNAi pathway in the context of a chromosomally integrated viral long terminal repeat (LTR using a CD4(+ T-cell line, Jurkat. Transcription factor profiling of the HTLV-1 LTR stably integrated T-cell clone transfected with Tax demonstrates increased activation of substrates and factors associated with chromatin remodeling complexes. Using a miRNA microarray and bioinformatics experimental approach, Tax was also shown to downregulate the expression of miRNAs associated with the translational regulation of factors required for chromatin remodeling. These observations were validated with selected miRNAs and an HTLV-1 infected T cells line, MT-2. miR-149 and miR-873 were found to be capable of directly targeting p300 and p/CAF, chromatin remodeling factors known to play critical role in HTLV-1 pathogenesis. Overall, these results are first in line establishing HTLV-1/Tax-miRNA-chromatin concept and open new avenues toward understanding retroviral latency and/or replication in a given cell type.

  16. Chromosome Aberrations by Heavy Ions

    Science.gov (United States)

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  17. A case of trisomy of chromosome 15

    OpenAIRE

    Coldwell, S; Fitzgerald, B.; Semmens, J.M.; Ede, R; Bateman, C

    1981-01-01

    We describe a case of trisomy of chromosome 15 in an infant who presented at birth with numerous abnormalities. As far as we are aware this chromosomal abnormality has not been described before. On the basis of this one case there appear to be no features which are specific to this chromosomal abnormality.

  18. [Leptin and hypothalamus-hypophysis-thyroid axis].

    Science.gov (United States)

    Riccioni, G; Menna, V; Lambo, M S; Della Vecchia, R; Di Ilio, C; De Lorenzo, A; D'Orazio, N

    2004-01-01

    The leptin system is a major regulator of food intake and metabolic rate. The leptin, an adipose tissue hormone whose plasma levels reflect energy stores, plays an important rule in the pathogenesis of such eating disorders like bulimia and anorexia. Thyroid hormones are major regulators of energy homeostasis. It is possible that leptin and thyroid hormone exert their actions on thermogenesis and energy metabolism via the same common effector patways. Leptin influences feedback regulation of the hypotalamic TRH-secreting neurons by thyroid hormone. Low serum levels of thyroid hormones reflect a dysfunction of the hypotalamic-pituitary-thyroid (HPT) and hypotalamic-pituitary-adrenal (HPA) axis in patients with nervosa anorexia. Neuroendocrine effects of leptin include effects on the HPT and HPA axis. The aim of this work is to evaluated the interactions between leptina and HPT axis on the basis of recent published works and reviews in literature. PMID:15147079

  19. New Urban Vertical Axis Wind Turbine Design

    Directory of Open Access Journals (Sweden)

    Alexandru-Mihai CISMILIANU

    2015-12-01

    Full Text Available This paper develops a different approach for enhancing the performance of Vertical Axis Wind Turbines for the use in the urban or rural environment and remote isolated residential areas. Recently the vertical axis wind turbines (VAWT have become more attractive due to the major advantages of this type of turbines in comparison to the horizontal axis wind turbines. We aim to enhance the overall performance of the VAWT by adding a second set of blades (3 x 2=6 blades following the rules of biplane airplanes. The model has been made to operate at a maximum power in the range of the TSR between 2 to 2.5. The performances of the VAWT were investigated numerically and experimentally and justify the new proposed design.

  20. Diffuser Augmented Horizontal Axis Tidal Current Turbines

    Directory of Open Access Journals (Sweden)

    Nasir Mehmood

    2012-09-01

    Full Text Available The renewal energy technologies are increasingly popular to ensure future energy sustenance and address environmental issues. The tides are enormous and consistent untapped resource of renewable energy. The growing interest in exploring tidal energy has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The tidal energy industry is undergoing an increasing shift towards diffuser augmented turbines. The reason is the higher power output of diffuser augmented turbines compared to conventional open turbines. The purpose of this study is to present a comprehensive review of diffuser augmented horizontal axis tidal current turbines. The components, relative advantages, limitations and design parameters of diffuser augmented horizontal axis tidal current turbines are presented in detail. CFD simulation of NACA 0016 airfoil is carried out to explore its potential for designing a diffuser. The core issues associated with diffuser augmented horizontal axis tidal current turbines are also discussed.

  1. Modular off-axis solar concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Plesniak, Adam P; Hall, John C

    2015-01-27

    A solar concentrator including a housing defining a vertical axis and including a receiving wall connected to a reflecting wall to define an internal volume and an opening into the internal volume, wherein the reflecting wall defines at least one primary optical element, and wherein at least a portion of the reflecting wall includes a layer of reflective material, the housing further including a cover connected to the receiving wall and the reflecting wall to seal the opening, and at least one receiver mounted on the receiving wall such that a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, the receiver including at least one photovoltaic cell.

  2. Protective role of heme oxygenase-1 in atrial remodeling.

    Science.gov (United States)

    Yeh, Yung-Hsin; Hsu, Lung-An; Chen, Ying-Hwa; Kuo, Chi-Tai; Chang, Gwo-Jyh; Chen, Wei-Jan

    2016-09-01

    Structural and electrical remodeling in the atrium constitutes the main feature of atrial fibrillation (AF), which is characterized by increased oxidative stress. Heme oxygenase-1 (HO-1) is a potent anti-oxidant system that may provide protection against various oxidative stress-related diseases. The aim of this study is to investigate whether HO-1 has a protective effect on AF-related remodeling. Cultured atrium-derived myocytes (HL-1 cell line) were used to evaluate tachypacing-induced oxidative stress, structural, and electrical remodeling. Transforming growth factor-β (TGF-β) was utilized to assess collagen (a main fibrosis-related protein) expression in atrial fibroblasts. Tachypacing in HL-1 myocytes and treatment of atrial fibroblasts with TGF-β enhanced the expression of HO-1, both of which were mediated by the activation of nuclear factor erythroid-2-related factor 2. Over-expression of HO-1 in HL-1 cells attenuated tachypacing-induced oxidative stress, myofibril degradation, down-regulation of L-type calcium channel, and shortening of action potential duration. Furthermore, HO-1 over-expression in atrial fibroblasts blocked the up-regulation of collagen by TGF-β, implicating a protective role of HO-1 in structural and electrical remodeling in the atrium. In vivo, HO-1(-/-) mice exhibited a higher degree of oxidative stress, myofibril degradation, and collagen deposit in their atria than wild-type mice. Moreover, burst atrial pacing induced a greater susceptibility to AF in HO-1(-/-) mice than in wild-type mice. In conclusion, a negative-feedback regulation of HO-1 in activated atrial myocytes and fibroblasts may provide protection against AF-related remodeling and AF development. PMID:27562817

  3. Aeroelastically coupled blades for vertical axis wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Paquette, Joshua; Barone, Matthew F.

    2016-02-23

    Various technologies described herein pertain to a vertical axis wind turbine blade configured to rotate about a rotation axis. The vertical axis wind turbine blade includes at least an attachment segment, a rear swept segment, and optionally, a forward swept segment. The attachment segment is contiguous with the forward swept segment, and the forward swept segment is contiguous with the rear swept segment. The attachment segment includes a first portion of a centroid axis, the forward swept segment includes a second portion of the centroid axis, and the rear swept segment includes a third portion of the centroid axis. The second portion of the centroid axis is angularly displaced ahead of the first portion of the centroid axis and the third portion of the centroid axis is angularly displaced behind the first portion of the centroid axis in the direction of rotation about the rotation axis.

  4. Solar rotating magnetic dipole?. [around axis perpendicular to rotation axis of the sun

    Science.gov (United States)

    Antonucci, E.

    1974-01-01

    A magnetic dipole rotating around an axis perpendicular to the rotation axis of the sun can account for the characteristics of the surface large-scale solar magnetic fields through the solar cycle. The polarity patterns of the interplanetary magnetic field, predictable from this model, agree with the observed interplanetary magnetic sector structure.

  5. Generator design for vertical axis wind turbine

    OpenAIRE

    Schüller, Espen Samuelsen

    2010-01-01

    The optimization process for generators are often done for rated speeds and torques. This thesis will discuss and show optimization of a vertical axis wind turbine generator that has a given wind profile. Although the rated power of the turbine is at winds of about 10 m/s, the wind is mostly at 4-6 m/s, thus needing a generator that has high efficiencies also at lower speeds and torques.Vertical axis wind turbine does not use blade pitching as the horizontal ones do and the torque and speed c...

  6. Lift Augmentation for Vertical Axis Wind Turbines

    OpenAIRE

    Gerald M Angle II; Mary Ann Clarke

    2010-01-01

    The concept of harnessing wind power has been around for centuries, and is first recorded by the Persians in 900 AD. These early uses of wind power were for the processing of food, particularly grinding grains, and consisted of stationary blades around a horizontal axis, the precursor to today’s horizontal axis wind turbines (HAWT). Technology for these wind mills was essentially the same until the 1930’s when advances in aircraft propeller theories were applied to the blades of the turbine. ...

  7. Chromosomal instability in Streptomyces avermitilis: major deletion in the central region and stable circularized chromosome

    Directory of Open Access Journals (Sweden)

    Wen Ying

    2010-07-01

    Full Text Available Abstract Background The chromosome of Streptomyces has been shown to be unstable, frequently undergoing gross chromosomal rearrangements. However, the mechanisms underlying this phenomenon remain unclear, with previous studies focused on two chromosomal ends as targets for rearrangements. Here we investigated chromosomal instability of Streptomyces avermitilis, an important producer of avermectins, and characterized four gross chromosomal rearrangement events, including a major deletion in the central region. The present findings provide a valuable contribution to the mechanistic study of genetic instability in Streptomyces. Results Thirty randomly-selected "bald" mutants derived from the wild-type strain all contained gross chromosomal rearrangements of various types. One of the bald mutants, SA1-8, had the same linear chromosomal structure as the high avermectin-producing mutant 76-9. Chromosomes of both strains displayed at least three independent chromosomal rearrangements, including chromosomal arm replacement to form new 88-kb terminal inverted repeats (TIRs, and two major deletions. One of the deletions eliminated the 36-kb central region of the chromosome, but surprisingly did not affect viability of the cells. The other deletion (74-kb was internal to the right chromosomal arm. The chromosome of another bald mutant, SA1-6, was circularized with deletions at both ends. No obvious homology was found in all fusion sequences. Generational stability analysis showed that the chromosomal structure of SA1-8 and SA1-6 was stable. Conclusions Various chromosomal rearrangements, including chromosomal arm replacement, interstitial deletions and chromosomal circularization, occurred in S. avermitilis by non-homologous recombination. The finding of an inner deletion involving in the central region of S. avermitilis chromosome suggests that the entire Streptomyces chromosome may be the target for rearrangements, which are not limited, as previously

  8. The origin of human chromosome 2 analyzed by comparative chromosome mapping with a DNA microlibrary

    OpenAIRE

    Wienberg, Johannes; Jauch, Anna; Lüdecke, H J; Senger, G; Horsthemke, B; Claussen, U; Cremer, Thomas; Arnold, N.; Lengauer, Christoph

    1994-01-01

    Fluorescencein situ hybridization (FISH) of microlibraries established from distinct chromosome subregions can test the evolutionary conservation of chromosome bands as well as chromosomal rearrangements that occurred during primate evolution and will help to clarify phylogenetic relationships. We used a DNA library established by microdissection and microcloning from the entire long arm of human chromosome 2 for fluorescencein situ hybridization and comparative mapping of the chromosomes of ...

  9. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei;

    2014-01-01

    driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... evolved very recently. CONCLUSIONS: In conclusion, we uncover that the sequence and expression patterns of Z chromosome genes covary with their ages of becoming Z-linked. In contrast to the mammalian X chromosomes, such patterns are mainly driven by mutational bias and genetic drift in birds, due...... to the opposite sex-biased inheritance of Z vs. X....

  10. Holoprosencephaly due to numeric chromosome abnormalities.

    Science.gov (United States)

    Solomon, Benjamin D; Rosenbaum, Kenneth N; Meck, Jeanne M; Muenke, Maximilian

    2010-02-15

    Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been reported. Such chromosome number abnormalities are almost universally fatal early in gestation or in infancy. Clinical features of specific chromosome number abnormalities may be recognized by phenotypic manifestations in addition to the HPE. PMID:20104610

  11. Novel insights into mitotic chromosome condensation

    Science.gov (United States)

    Piskadlo, Ewa; Oliveira, Raquel A.

    2016-01-01

    The fidelity of mitosis is essential for life, and successful completion of this process relies on drastic changes in chromosome organization at the onset of nuclear division. The mechanisms that govern chromosome compaction at every cell division cycle are still far from full comprehension, yet recent studies provide novel insights into this problem, challenging classical views on mitotic chromosome assembly. Here, we briefly introduce various models for chromosome assembly and known factors involved in the condensation process (e.g. condensin complexes and topoisomerase II). We will then focus on a few selected studies that have recently brought novel insights into the mysterious way chromosomes are condensed during nuclear division.

  12. Research of misalignment between dithered ring laser gyro angle rate input axis and dither axis

    Science.gov (United States)

    Li, Geng; Wu, Wenqi; FAN, Zhenfang; LU, Guangfeng; Hu, Shaomin; Luo, Hui; Long, Xingwu

    2014-12-01

    The strap-down inertial navigation system (SINS), especially the SINS composed by dithered ring laser gyroscope (DRLG) is a kind of equipment, which providing high reliability and performance for moving vehicles. However, the mechanical dither which is used to eliminate the "Lock-In" effect can cause vibration disturbance to the INS and lead to dithering coupling problem in the inertial measurement unit (IMU) gyroscope triad, so its further application is limited. Among DRLG errors between the true gyro rotation rate and the measured rotation rate, the frequently considered one is the input axis misalignment between input reference axis which is perpendicular to the mounting surface and gyro angular rate input axis. But the misalignment angle between DRLG dither axis and gyro angular rate input axis is often ignored by researchers, which is amplified by dither coupling problem and that would lead to negative effects especially in high accuracy SINS. In order to study the problem more clearly, the concept of misalignment between DRLG dither axis and gyro angle rate input axis is researched. Considering the error of misalignment is of the order of 10-3 rad. or even smaller, the best way to measure it is using DRLG itself by means of an angle exciter as an auxiliary. In this paper, the concept of dither axis misalignment is explained explicitly firstly, based on this, the frequency of angle exciter is induced as reference parameter, when DRLG is mounted on the angle exciter in a certain angle, the projections of angle exciter rotation rate and mechanical oscillation rate on the gyro input axis are both sensed by DRLG. If the dither axis has misalignment error with the gyro input axis, there will be four major frequencies detected: the frequency of angle exciter, the dither mechanical frequency, sum and difference frequencies of the former two frequencies. Then the amplitude spectrum of DRLG output signal obtained by the using LabVIEW program. if there are only angle

  13. Transient Microgeographic Clines during B Chromosome Invasion.

    Science.gov (United States)

    Camacho, Juan Pedro M; Shaw, Michael W; Cabrero, Josefa; Bakkali, Mohammed; Ruíz-Estévez, Mercedes; Ruíz-Ruano, Francisco J; Martín-Blázquez, Rubén; López-León, María Dolores

    2015-11-01

    The near-neutral model of B chromosome evolution predicts that the invasion of a new population should last some tens of generations, but the details on how it proceeds in real populations are mostly unknown. Trying to fill this gap, we analyze here a natural population of the grasshopper Eyprepocnemis plorans at three time points during the last 35 years. Our results show that B chromosome frequency increased significantly during this period and that a cline observed in 1992 had disappeared in 2012 once B chromosome frequency reached an upper limit at all sites sampled. This indicates that, during B chromosome invasion, transient clines for B chromosome frequency are formed at the invasion front on a microgeographic scale. Computer simulation experiments showed that the pattern of change observed for genotypic frequencies is consistent with the existence of B chromosome drive through females and selection against individuals with a high number of B chromosomes. PMID:26655780

  14. Mitosis. Microtubule detyrosination guides chromosomes during mitosis.

    Science.gov (United States)

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K; Magiera, Maria M; Zaytsev, Anatoly V; Pereira, Ana L; Janke, Carsten; Grishchuk, Ekaterina L; Maiato, Helder

    2015-05-15

    Before chromosomes segregate into daughter cells, they align at the mitotic spindle equator, a process known as chromosome congression. Centromere-associated protein E (CENP-E)/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically toward the equator. We found that congression of pole-proximal chromosomes depended on specific posttranslational detyrosination of spindle microtubules that point to the equator. In vitro reconstitution experiments demonstrated that CENP-E-dependent transport was strongly enhanced on detyrosinated microtubules. Blocking tubulin tyrosination in cells caused ubiquitous detyrosination of spindle microtubules, and CENP-E transported chromosomes away from spindle poles in random directions. Thus, CENP-E-driven chromosome congression is guided by microtubule detyrosination. PMID:25908662

  15. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    Directory of Open Access Journals (Sweden)

    Daniela Mierla

    2012-06-01

    Full Text Available Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, karyotype analysis by G-banding was performed from peripheral blood in 967 women infertility. Results: Chromosomal abnormalities were found to 79 women (8,17%. The percentage of chromosomal abnormalities in the studied population correlates with the data in the literature. Chromosomal abnormalities could play the important role in etiology of infertility and are more frequently detected in this group of patients compared to general population. In the infertile couples balanced chromosomal abnormalities are the main cause of spontaneous abortions.

  16. [The evolution of human Y chromosome].

    Science.gov (United States)

    Yang, Xianrong; Wang, Meiqin; Li, Shaohua

    2014-09-01

    The human Y chromosome is always intriguing for researchers, because of its role in gender determination and its unusual evolutionary history. The Y chromosome evolves from an autosome, and its evolution has been characterized by massive gene decay. The lack of recombination and protein-coding genes and high content of repetitive sequences have hindered the progress in our understanding of the Y chromosome biology. Recently, with the advances in comparative genomics and sequencing technology, the research on Y chromosome has become a hotspot, with an intensified debate about Y-chromosome final destination resulting from degeneration. This review focuses on the structure, inheritance characteristics, gene content, and the origin and evolution of Y chromosome. We also discuss the long-term destiny of Y chromosome. PMID:25252301

  17. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate this...... and reliable method enabled us to start the analysis on the distribution of various chromosomal loci inside slowly growing cells. With the actual counting and measuring no longer being any problem we could easily analyze 14 loci distributed on the E.coli chromosome. More than 15.000 cells were...... on the P1 par system. Using the new system, which is based on the pMT1 par system from Yersenia pestis, we labeled loci on opposite sides of the E.coli chromosome simultaneously and were able to show that the E.coli chromosome is organized with one chromosomal arm in each cell half. This astounding...

  18. Microdissection and chromosome painting of the alien chromosome in an addition line of wheat-Thinopyrum intermedium

    Science.gov (United States)

    The chromosome painting is an efficient tool for chromosome research. However, plant chromosome painting is relatively underdeveloped. In this study, chromosome painting was developed and used to identify alien chromosomes in TAi-27, a wheat-Thinopyrum intermedium addition line, and chromosomes of...

  19. The Trading Axis in Irkutsk Downtown

    Directory of Open Access Journals (Sweden)

    Elena Grigoryeva

    2015-12-01

    Full Text Available The article reveals a linear concentration of the trading function in the historical center of Irkutsk. It features historical prerequisites and continuation of the tradition in the post-Soviet period, given the conversion of plants and factories. The article analyses the current state and prospects of modernization of the trading axis with its transformation into a modern public space.

  20. Resolution of a triple axis spectrometer

    DEFF Research Database (Denmark)

    Nielsen, Mourits; Bjerrum Møller, Hans

    A new method for obtaining the resolution function for a triple-axis neutron spectrometer is described, involving a combination of direct measurement and analytical calculation. All factors which contribute to the finite resolution of the instrument may be taken into account, and Gaussian or...

  1. Triple-axis spectrometer DruechaL

    International Nuclear Information System (INIS)

    DruechaL is a triple-axis spectrometer located at a cold guide. The characteristics of guide and instrument allow the use of a broad spectral range of neutrons. The resolution in momentum and energy transfer can be tuned to match the experimental requirements by using either collimators or focusing systems (monochromator, antitrumpet, analyser). (author) figs., tabs., refs

  2. Fibrous dysplasia in axis treated with vertebroplasty

    Directory of Open Access Journals (Sweden)

    Kadir Kotil

    2010-01-01

    Full Text Available Vertebroplasty of the axis is a challenging procedure, and little is known about its therapeutic outcome. Cervical fibrous dysplasia with a distinct cyst is a rare entity and few cases have been reported in the literature. A 55-year-old man with fibrous dysplasia of axis presented with severe neck pain and left arm since six months. Computed tomography and magnetic resonance imaging revealed an expansile, destructive lesion involving the axis, and no spinal cord. He was submitted to retropharyngeal surgery and the lesion was fulled by vertebroplasty. Microscopic examination was consistent with the diagnosis of monostotic fibrous dysplasia. After the surgery no recurrence was observed. The patient had remarkable improvement in clinical relief of neck pain at 1-year follow-up. Although there are descriptions of vertebral fibrous dysplasia, this is the 13th case of monostotic fibrous dysplasia of the cervical spine, and the 3rd case of the axis described in the literature. The unique case who had treated with ope vertebroplasty.

  3. Horizontal Axis Levitron--A Physics Demonstration

    Science.gov (United States)

    Michaelis, Max M.

    2014-01-01

    After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the "spignet". Precession is fundamental to nuclear magnetic…

  4. Thyroid axis alterations in childhood obesity.

    Science.gov (United States)

    Gertig, Anna M; Niechciał, Elżbieta; Skowrońska, Bogda

    2012-01-01

    In recent years researchers have become increasingly interested in the particular relation between the function of the thyroid gland and the body mass in the population of obese children. Numerous studies have been conducted and the literature on the related issues has been abounding. Several thereof have strived at pinpointing a significant link between the function of the thyroid axis and the body mass. Yet, it still remains to be clarified whether these subtle changes in the level of thyroid hormones and TSH observed in childhood obesity are responsible for the increased body mass or rather they represent a secondary phenomenon. The mechanism most often put forward by the researchers that links obesity to thyroid function is the increased level of leptin, which affects neurones in the hypothalamus and the thyroid axis causing TRH and TSH secretion. The body mass is positively correlated with serum leptin and elevated level of leptin is connected with an increase in TSH level. However, there is still controversy whether these inconspicuous differences observed in thyroid axis merit the treatment with thyroxine since these changes seem to constitute a consequence rather than a cause of obesity. Therefore, as most authors postulate, primary importance should be placed on lifestyle changes and body weight reduction leaving substitutive treatment as a supplementary option. The purpose of this review is to present the most current issues on child obesity and the related malfunction of the thyroid axis through an overview of international publications from the years 1996-2011. PMID:23146791

  5. Tennis Rackets and the Parallel Axis Theorem

    Science.gov (United States)

    Christie, Derek

    2014-01-01

    This simple experiment uses an unusual graph straightening exercise to confirm the parallel axis theorem for an irregular object. Along the way, it estimates experimental values for g and the moment of inertia of a tennis racket. We use Excel to find a 95% confidence interval for the true values.

  6. Triple-axis spectrometer DruechaL

    Energy Technology Data Exchange (ETDEWEB)

    Buehrer, W.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    DruechaL is a triple-axis spectrometer located at a cold guide. The characteristics of guide and instrument allow the use of a broad spectral range of neutrons. The resolution in momentum and energy transfer can be tuned to match the experimental requirements by using either collimators or focusing systems (monochromator, antitrumpet, analyser). (author) figs., tabs., refs.

  7. Vortex capturing vertical axis wind turbine

    International Nuclear Information System (INIS)

    An analytical-numerical study is presented for an innovative lift vertical axis turbine whose blades are designed with vortex trapping cavities that act as passive flow control devices. The unsteady flow field past one-bladed and two-bladed turbines is described by a combined analytical and numerical method based on conformal mapping and on a blob vortex method

  8. International workshop of chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ. Medical Center, Durham, NC (United States). Div. of Neurology); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1991-09-16

    This document summarizes the workshop on physical and genetic mapping of chromosome 19. The first session discussed the major disease loci found on the chromosome. The second session concentrated on reference families, markers and linkage maps. The third session concentrated on radiation hybrid mapping, somatic cell hybrid panels, macro restriction maps and YACs, followed by cDNA and long range physical maps. The fourth session concentrated on compiling consensus genetic and physical maps as well as discussing regions of conflict. The final session dealt with the LLNL cosmid contig database and comparative mapping of homologous regions of the human and mouse genomes, and ended with a discussion of resource sharing. 18 refs., 2 figs. (MHB)

  9. Detection of dinoflagellates by the light scattering properties of the chiral structure of their chromosomes

    International Nuclear Information System (INIS)

    One of the most prominent properties of dinoflagellates is their large sized and highly chromosome-laden nucleus, which contains dozens of cylindrically shaped chromosomes. With such high chromatic concentration, these chromosomes condense into ordered helical structures and were claimed to be responsible for the large circular polarization effects observed in the light scattering from dinoflagellates. In previous research, a thin helix model of a chromosome was used to compare the Discrete Dipole Approximation (DDA) and the analytical Born approximation calculations. However, for such a simplified model only modest qualitative agreements with experimental measurements were achieved. Moreover, only one chromosome in one nucleus was simulated, overlooking the effects of interactions between chromosomes. In this work, we adopt the helical plywood liquid crystal model with a capsule shape, in which parallel fibrils lie in plains perpendicular to the helix axis and the orientations of these fibrils twist at a constant angle between two neighboring layers. The ADDA code is applied to calculate the 16 Mueller matrix elements of light scattering from a single chromosome and from the nucleus, which is composed of a collection of randomly positioned and randomly orientated chromosomes. Special attention is paid to the S14 Mueller matrix element, which describes the ability of differentiating left and right circularly polarized light. Our results show that large S14 back scattering signals from the dinoflagellate nucleus results from the underlying helical structures of its chromosomes. These signals are sensitive to the light wavelength and pitch of the chromatic helix, the latter of which is species specific. Therefore, detecting back scattering S14 signal could be a promising method to monitor dinoflagellates such as Karenia brevis, the causal agent of the Florida red tide. -- Highlights: ► The nucleus of dinoflagellate is modeled by using the Plywood cholesteric model

  10. Baseline chromosome aberrations in children

    Czech Academy of Sciences Publication Activity Database

    Merlo, D.F.; Ceppi, M.; Stagi, E.; Bocchini, V.; Šrám, Radim; Rössner st., Pavel

    2007-01-01

    Roč. 172, - (2007), s. 60-67. ISSN 0378-4274 Grant ostatní: EU(EU) 2002-02198; EU(EU) 2005-016320 Institutional research plan: CEZ:AV0Z50390512 Source of funding: R - rámcový projekt EK ; R - rámcový projekt EK Keywords : chromosome aberrations * children * molecular epidemiology Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.826, year: 2007

  11. Clonality - X Chromosome Inactivation Assay

    OpenAIRE

    sprotocols

    2014-01-01

    Author: Molecular Profiling Initiative, NCI This method was successful in our lab using prostate tissue and for our specific objectives. Investigators must be aware that they will need to tailor the following protocol for their own research objectives and tissue under study. Investigators can utilize X chromosome inactivation (methylation) to determine the clonality status of a tumor or premalignant lesion in females. The technique is based on a methylation-sensitive restriction enzym...

  12. Hobo transposons causing chromosomal breakpoints.

    OpenAIRE

    Ladevèze, V; Aulard, S.; Chaminade, N; Périquet, G; Lemeunier, F

    1998-01-01

    Several laboratory surveys have shown that transposable elements (TEs) can cause chromosomal breaks and lead to inversions, as in dysgenic crosses involving P-elements. However, it is not presently clear what causes inversions in natural populations of Drosophila. The only direct molecular studies must be taken as evidence against the involvement of mobile elements. Here, in Drosophila lines transformed with the hobo transposable element, and followed for 100 generations, we show the appearan...

  13. Chromosomal instability determines taxane response

    OpenAIRE

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C.; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang

    2009-01-01

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells....

  14. Chromosome aberration assays in Allium

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  15. Chromosome rearrangements and transposable elements.

    Science.gov (United States)

    Lonnig, Wolf-Ekkehard; Saedler, Heinz

    2002-01-01

    There has been limited corroboration to date for McClintock's vision of gene regulation by transposable elements (TEs), although her proposition on the origin of species by TE-induced complex chromosome reorganizations in combination with gene mutations, i.e., the involvement of both factors in relatively sudden formations of species in many plant and animal genera, has been more promising. Moreover, resolution is in sight for several seemingly contradictory phenomena such as the endless reshuffling of chromosome structures and gene sequences versus synteny and the constancy of living fossils (or stasis in general). Recent wide-ranging investigations have confirmed and enlarged the number of earlier cases of TE target site selection (hot spots for TE integration), implying preestablished rather than accidental chromosome rearrangements for nonhomologous recombination of host DNA. The possibility of a partly predetermined generation of biodiversity and new species is discussed. The views of several leading transposon experts on the rather abrupt origin of new species have not been synthesized into the macroevolutionary theory of the punctuated equilibrium school of paleontology inferred from thoroughly consistent features of the fossil record. PMID:12429698

  16. Comparative analysis of sex chromosomes in Leporinus species (Teleostei, Characiformes) using chromosome painting

    Science.gov (United States)

    2013-01-01

    Background The Leporinus genus, belonging to the Anostomidae family, is an interesting model for studies of sex chromosome evolution in fish, particularly because of the presence of heteromorphic sex chromosomes only in some species of the genus. In this study we used W chromosome-derived probes in a series of cross species chromosome painting experiments to try to understand events of sex chromosome evolution in this family. Results W chromosome painting probes from Leporinus elongatus, L. macrocephalus and L. obtusidens were hybridized to each others chromosomes. The results showed signals along their W chromosomes and the use of L. elongatus W probe against L. macrocephalus and L. obtusidens also showed signals over the Z chromosome. No signals were observed when the later aforementioned probe was used in hybridization procedures against other four Anostomidae species without sex chromosomes. Conclusions Our results demonstrate a common origin of sex chromosomes in L. elongatus, L. macrocephalus and L. obtusidens but suggest that the L. elongatus chromosome system is at a different evolutionary stage. The absence of signals in the species without differentiated sex chromosomes does not exclude the possibility of cryptic sex chromosomes, but they must contain other Leporinus W sequences than those described here. PMID:23822802

  17. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    Science.gov (United States)

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Abstract B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  18. Chromosomal divergence and evolutionary inferences in Rhodniini based on the chromosomal location of ribosomal genes

    Directory of Open Access Journals (Sweden)

    Sebastian Pita

    2013-05-01

    Full Text Available In this study, we used fluorescence in situ hybridisation to determine the chromosomal location of 45S rDNA clusters in 10 species of the tribe Rhodniini (Hemiptera: Reduviidae: Triatominae. The results showed striking inter and intraspecific variability, with the location of the rDNA clusters restricted to sex chromosomes with two patterns: either on one (X chromosome or both sex chromosomes (X and Y chromosomes. This variation occurs within a genus that has an unchanging diploid chromosome number (2n = 22, including 20 autosomes and 2 sex chromosomes and a similar chromosome size and genomic DNA content, reflecting a genome dynamic not revealed by these chromosome traits. The rDNA variation in closely related species and the intraspecific polymorphism in Rhodnius ecuadoriensis suggested that the chromosomal position of rDNA clusters might be a useful marker to identify recently diverged species or populations. We discuss the ancestral position of ribosomal genes in the tribe Rhodniini and the possible mechanisms involved in the variation of the rDNA clusters, including the loss of rDNA loci on the Y chromosome, transposition and ectopic pairing. The last two processes involve chromosomal exchanges between both sex chromosomes, in contrast to the widely accepted idea that the achiasmatic sex chromosomes of Heteroptera do not interchange sequences.

  19. Synaptic remodeling of neuronal circuits in early retinal degeneration

    Directory of Open Access Journals (Sweden)

    Florentina eSoto

    2015-10-01

    Full Text Available Photoreceptor degenerations are a major cause of blindness and among the most common forms of neurodegeneration in humans. Studies of mouse models revealed that synaptic dysfunction often precedes photoreceptor degeneration, and that abnormal synaptic input from photoreceptors to bipolar cells causes circuits in the inner retina to become hyperactive. Here, we provide a brief overview of frequently used mouse models of photoreceptor degenerations. We then discuss insights into circuit remodeling triggered by early synaptic dysfunction in the outer and hyperactivity in the inner retina. We discuss these insights in the context of other experimental manipulations of synaptic function and activity. Knowledge of the plasticity and early remodeling of retinal circuits will be critical for the design of successful vision rescue strategies.

  20. Role of Cannabinoids in the Regulation of Bone Remodelling

    Directory of Open Access Journals (Sweden)

    Aymen I Idris

    2012-11-01

    Full Text Available The endocannabinoid system plays a key role in regulating a variety of physiological processes such as appetite control and energy balance, pain perception, and immune responses. Recent studies have implicated the endocannabinoid system in the regulation of bone cell activity and bone remodelling. These studies showed that endogenous cannabinoid ligands, cannabinoid receptors and the enzymes responsible for ligand synthesis and breakdown all play important roles in bone mass and in the regulation of bone disease. These findings suggest that the endocannabinoid pathway could be of value as a therapeutic target for the prevention and treatment of bone diseases. Here, we review the role of the skeletal endocannabinoid system in the regulation of bone remodelling in health and disease.

  1. Intradialytic Hypotension and Cardiac Remodeling: A Vicious Cycle

    Directory of Open Access Journals (Sweden)

    Chia-Ter Chao

    2015-01-01

    Full Text Available Hemodynamic instability during hemodialysis is a common but often underestimated issue in the nephrologist practice. Intradialytic hypotension, namely, a decrease of systolic or mean blood pressure to a certain level, prohibits the safe and smooth achievement of ultrafiltration and solute removal goal in chronic dialysis patients. Studies have elucidated the potential mechanisms involved in the development of Intradialytic hypotension, including excessive ultrafiltration and loss of compensatory mechanisms for blood pressure maintenance. Cardiac remodeling could also be one important piece of the puzzle. In this review, we intend to discuss the role of cardiac remodeling, including left ventricular hypertrophy, in the development of Intradialytic hypotension. In addition, we will also provide evidence that a bidirectional relationship might exist between Intradialytic hypotension and left ventricular hypertrophy in chronic dialysis patients. A more complete understanding of the complex interactions in between could assist the readers in formulating potential solutions for the reduction of both phenomena.

  2. Probabilistic Study of Bone Remodeling Using Finite Element Analysis

    Science.gov (United States)

    Werner, C.; Gorla, R. S. R.

    2013-08-01

    The dynamic bone remodeling process is a computationally challenging research area that struggles to understand the actual mechanisms. It has been observed that a mechanical stimulus in the bone greatly affects the remodeling process. A 3D finite element model of a femur is created and a probabilistic analysis is performed on the model. The probabilistic analysis measures the sensitivities of various parameters related to the material properties, geometric properties, and the three load cases defined as Single Leg Stance, Abduction, and Adduction. The sensitivity of each parameter is based on the calculated maximum mechanical stimulus and analyzed at various values of probabilities ranging from 0.001 to 0.999. The analysis showed that the parameters associated with the Single Leg Stance load case had the highest sensitivity with a probability of 0.99 and the angle of the force applied to the joint of the proximal femur had the overall highest sensitivity

  3. Synaptic remodeling of neuronal circuits in early retinal degeneration

    Science.gov (United States)

    Soto, Florentina; Kerschensteiner, Daniel

    2015-01-01

    Photoreceptor degenerations are a major cause of blindness and among the most common forms of neurodegeneration in humans. Studies of mouse models revealed that synaptic dysfunction often precedes photoreceptor degeneration, and that abnormal synaptic input from photoreceptors to bipolar cells causes circuits in the inner retina to become hyperactive. Here, we provide a brief overview of frequently used mouse models of photoreceptor degenerations. We then discuss insights into circuit remodeling triggered by early synaptic dysfunction in the outer and hyperactivity in the inner retina. We discuss these insights in the context of other experimental manipulations of synaptic function and activity. Knowledge of the plasticity and early remodeling of retinal circuits will be critical for the design of successful vision rescue strategies. PMID:26500497

  4. The solid state environment orchestrates embryonic development and tissue remodeling

    Science.gov (United States)

    Damsky, C. H.; Moursi, A.; Zhou, Y.; Fisher, S. J.; Globus, R. K.

    1997-01-01

    Cell interactions with extracellular matrix and with other cells play critical roles in morphogenesis during development and in tissue homeostasis and remodeling throughout life. Extracellular matrix is information-rich, not only because it is comprised of multifunctional structural ligands for cell surface adhesion receptors, but also because it contains peptide signaling factors, and proteinases and their inhibitors. The functions of these groups of molecules are extensively interrelated. In this review, three primary cell culture models are described that focus on adhesion receptors and their roles in complex aspects of morphogenesis and remodeling: the regulation of proteinase expression by fibronectin and integrins in synovial fibroblasts; the regulation of osteoblast differentiation and survival by fibronectin, and the regulation of trophoblast differentiation and invasion by integrins, cadherins and immunoglobulin family adhesion receptors.

  5. Compensatory Effect between Aortic Stiffening and Remodelling during Ageing.

    Directory of Open Access Journals (Sweden)

    Andrea Guala

    Full Text Available The arterial tree exhibits a complex spatio-temporal wave pattern, whose healthy behaviour depends on a subtle balance between mechanical and geometrical properties. Several clinical studies demonstrated that such a balance progressively breaks down during ageing, when the aorta stiffens and remodels by increasing its diameter. These two degenerative processes however, have different impacts on the arterial wave pattern. They both tend to compensate for each other, thus reducing the detrimental effect they would have had if they had arisen individually. This remarkable compensatory mechanism is investigated by a validated multi-scale model, with the aim to elucidate how aortic stiffening and remodelling quantitatively impact the complex interplay between forward and reflected backward waves in the arterial network. We focus on the aorta and on the pressure at the ventricular-aortic interface, which epidemiological studies demonstrate to play a key role in cardiovascular diseases.

  6. Identification by R-banding and FISH of chromosome arms involved in Robertsonian translocations in several deer species.

    Science.gov (United States)

    Bonnet-Garnier, A; Claro, F; Thévenon, S; Gautier, M; Hayes, H

    2003-01-01

    We constructed and analyzed the RBG-banded karyotype of five deer species: Chital (Axis axis), White-lipped deer (Cervus albirostris), Rusa deer (Cervus timorensis russa), Sambar deer (Cervus unicolor) and Eld's deer (Cervus eldi siamensis). Among these five species, only Eld's deer had been previously karyotyped using R-banding. In order to identify all the chromosome correspondences with cattle and precisely which chromosome arms are involved in Robertsonian translocations, we compared the karyotypes of these five species with those of the closely related and well-characterized species, cattle (Bos taurus) and Vietnamese Sika deer (Cervus nippon pseudaxis). Among these six deer species (the five above plus the Vietnamese Sika deer), we found thirteen different Robertsonian translocations involving nineteen different chromosome arms. Thirteen chromosome arms were identified by comparison of R-banding patterns only and the remaining six were either confirmed or identified by FISH-mapping of bovine or caprine probes previously localized in cattle. Finally, we observed that five of the thirteen Robertsonian translocations are shared by at least two species and that some chromosome arms are more frequently involved in Robertsonian translocations than others. PMID:14606627

  7. Specificity analysis of lectins and antibodies using remodeled glycoproteins

    OpenAIRE

    Iskratsch, Thomas; Braun, Andreas; Paschinger, Katharina; Wilson, Iain B. H.

    2009-01-01

    Due to their ability to bind specifically to certain carbohydrate sequences, lectins are a frequently used tool in cytology, histology, and glycan analysis but also offer new options for drug targeting and drug delivery systems. For these and other potential applications, it is necessary to be certain as to the carbohydrate structures interacting with the lectin. Therefore, we used glycoproteins remodeled with glycosyltransferases and glycosidases for testing specificities of lectins from Ale...

  8. Vascular remodeling as compensatory changes in different degrees of varicocele

    Directory of Open Access Journals (Sweden)

    E. S. Severgina

    2013-01-01

    Full Text Available We investigated biosises obtained from children with different varicocele stages and showed the possibility of remodeling development in different type vein walls. Most typical changes were found in the third type vein walls – multiple rolls, composed of muscular and collagen bundles; in the larger first and second type veins markers of arterialization were seen. These processes are the manifestations of adaptive response, which is connected with elevated venous pressure; they can improve testicular hemodynamic.

  9. Vascular remodeling as compensatory changes in different degrees of varicocele

    Directory of Open Access Journals (Sweden)

    E. S. Severgina

    2014-11-01

    Full Text Available We investigated biosises obtained from children with different varicocele stages and showed the possibility of remodeling development in different type vein walls. Most typical changes were found in the third type vein walls – multiple rolls, composed of muscular and collagen bundles; in the larger first and second type veins markers of arterialization were seen. These processes are the manifestations of adaptive response, which is connected with elevated venous pressure; they can improve testicular hemodynamic.

  10. Quantitative computed tomography imaging of airway remodeling in severe asthma

    OpenAIRE

    Grenier, Philippe A.; Fetita, Catalin I.; Brillet, Pierre-Yves

    2016-01-01

    Asthma is a heterogeneous condition and approximately 5–10% of asthmatic subjects have severe disease associated with structure changes of the airways (airway remodeling) that may develop over time or shortly after onset of disease. Quantitative computed tomography (QCT) imaging of the tracheobronchial tree and lung parenchyma has improved during the last 10 years, and has enabled investigators to study the large airway architecture in detail and assess indirectly the small airway structure. ...

  11. The Role of the Epithelium in Airway Remodeling in Asthma

    OpenAIRE

    Davies, Donna E.

    2009-01-01

    The bronchial epithelium is the barrier to the external environment and plays a vital role in protection of the internal milieu of the lung. It functions within the epithelial-mesenchymal trophic unit to control the local microenvironment and help maintain tissue homeostasis. However, in asthma, chronic perturbation of these homeostatic mechanisms leads to alterations in the structure of the airways, termed remodeling. Damage to the epithelium is now recognized to play a key role in driving a...

  12. Extension and internal remodel [The Old School House, Northumberland

    OpenAIRE

    Elliott, Benjamin; Elliott, Lynsey

    2010-01-01

    A large domestic property with a disproportionately small existing kitchen resulted in the clients desire to extend. The project afforded us the opportunity to internally remodel the dark cellular service spaces to the rear of the property in order to rationalise the internal circulation and combine unused floor space with the new open plan layout. Bringing natural light deep into the plan was a priority whilst maintaining the features of the existing external wall. A new timber cla...

  13. Remodeling of Calcium Handling in Human Heart Failure

    OpenAIRE

    Lou, Qing; Janardhan, Ajit; Efimov, Igor R.

    2012-01-01

    Heart failure (HF) is an increasing public health problem accelerated by a rapidly aging global population. Despite considerable progress in managing the disease, the development of new therapies for effective treatment of HF remains a challenge. To identify targets for early diagnosis and therapeutic intervention, it is essential to understand the molecular and cellular basis of calcium handling and the signaling pathways governing the functional remodeling associated with HF in humans. Calc...

  14. Porosity Defect Remodeling and Tensile Analysis of Cast Steel

    OpenAIRE

    Linfeng Sun; Ridong Liao; Wei Lu; Sibo Fu

    2016-01-01

    Tensile properties on ASTM A216 WCB cast steel with centerline porosity defect were studied with radiographic mapping and finite element remodeling technique. Non-linear elastic and plastic behaviors dependent on porosity were mathematically described by relevant equation sets. According to the ASTM E8 tensile test standard, matrix and defect specimens were machined into two categories by two types of height. After applying radiographic inspection, defect morphologies were mapped to the mid-s...

  15. BMP-2 Is Involved in Scleral Remodeling in Myopia Development

    OpenAIRE

    Honghui Li; Dongmei Cui; Feng Zhao; Lijun Huo; Jianmin Hu; Junwen Zeng

    2015-01-01

    The development of myopia is associated with scleral remodeling, but it is unclear which factors regulate this process. This study investigated bone morphogenetic protein-2 (BMP-2) expression in the sclera of guinea pigs with lens-induced myopia (LIM) and after recovery from myopia and evaluated the effect of BMP-2 on extracellular matrix (ECM) synthesis in human scleral fibroblasts (HSFs) cultured in vitro. Lens-induced myopia was brought about in two groups of guinea pigs (the lens-induced ...

  16. Thermally Induced Osteocyte Damage Initiates a Remodelling Signaling Cascade

    OpenAIRE

    Dolan, Eimear B.; Matthew G Haugh; Voisin, Muriel C.; David Tallon; McNamara, Laoise M.

    2015-01-01

    Thermal elevations experienced by bone during orthopaedic procedures, such as cutting and drilling, exothermal reactions from bone cement, and thermal therapies such as tumor ablation, can result in thermal damage leading to death of native bone cells (osteocytes, osteoblasts, osteoclasts and mesenchymal stem cells). Osteocytes are believed to be the orchestrators of bone remodeling, which recruit nearby osteoclast and osteoblasts to control resorption and bone growth in response to mechanica...

  17. Energy Efficiency Measures to Incorporate into Remodeling Projects

    Energy Technology Data Exchange (ETDEWEB)

    Liaukus, C.

    2014-12-01

    Energy improvements in a home are often approached as one concerted effort, beginning with a simple walk-through assessment or more in-depth energy audit and followed by the installation of recommended energy measures. While this approach allows for systems thinking to guide the efforts, comprehensive energy improvements of this nature are undertaken by a relatively small number of the households in our nation compared to more piecemeal remodeling efforts. Even when programs like the Weatherization Assistance Program and Home Performance with ENERGY STAR are considered, homes that have had a comprehensive energy makeover still represent a small fraction of the 111.1 million households. In this report, the U.S Department of Energy Building America Retrofit Alliance research team looks at the improvement of a home's energy performance in an opportunistic way: it examines what can be done to incorporate energy efficiency measures into general remodeling work and home repair projects. This allows for the possibility for people who would not normally pursue energy efficiency but will remodel their kitchen or re-side their home to improve their home's performance at the same time. There are challenges to this approach, not the least of which being that the work will take place over time in potentially many separate projects. The opportunity to improve a home's energy efficiency at one time expands or contracts with the scope of the remodel. As such, guidance on how to do each piece thoughtfully and with consideration for potential future projects, is critical.

  18. Silent Synapse-Based Circuitry Remodeling in Drug Addiction

    OpenAIRE

    Dong, Yan

    2015-01-01

    Exposure to cocaine, and likely other drugs of abuse, generates α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-silent glutamatergic synapses in the nucleus accumbens. These immature synaptic contacts evolve after drug withdrawal to redefine the neurocircuital properties. These results raise at least three critical questions: (1) what are the molecular and cellular mechanisms that mediate drug-induced generation of silent synapses; (2) how are neurocircuits remodeled upon genera...

  19. Beyond the Genome: Epigenetic Mechanisms in Lung Remodeling

    OpenAIRE

    Hagood, James S

    2014-01-01

    The lung develops from a very simple outpouching of the foregut into a highly complex, finely structured organ with multiple specialized cell types that are required for its normal physiological function. During both the development of the lung and its remodeling in the context of disease or response to injury, gene expression must be activated and silenced in a coordinated manner to achieve the tremendous phenotypic heterogeneity of cell types required for homeostasis and pathogenesis. Epige...

  20. Regulation of intracellular signaling by extracellular glycan remodeling

    OpenAIRE

    Parker, Randy B.; Kohler, Jennifer J.

    2010-01-01

    The plasma membrane of eukaryotic cells is coated with carbohydrates. By virtue of their extracellular position and recognizable chemical features, cell surface glycans mediate many receptor-ligand interactions. Recently, mammalian extracellular hydrolytic enzymes have been shown to modify the structure of cell surface glycans and consequently, alter their binding properties. These cell surface glycan remodeling events can cause rapid changes in critical signal transduction phenomena. This re...

  1. HGF/c-MET Axis in Tumor Microenvironment and Metastasis Formation

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    Anna Spina

    2015-01-01

    Full Text Available Tumor metastases are responsible for approximately 90% of all cancer-related deaths. Metastasis formation is a multistep process that requires acquisition by tumor cells of a malignant phenotype that allows them to escape from the primary tumor site and invade other organs. Each step of this mechanism involves a deep crosstalk between tumor cells and their microenvironment where the host cells play a key role in influencing metastatic behavior through the release of many secreted factors. Among these signaling molecules, Hepatocyte Growth Factor (HGF is released by many cell types of the tumor microenvironment to target its receptor c-MET within the cells of the primary tumor. Many studies reveal that HGF/c-MET axis is implicated in various human cancers, and genetic and epigenetic gain of functions of this signaling contributes to cancer development through a variety of mechanisms. In this review, we describe the specific types of cells in the tumor microenvironment that release HGF in order to promote the metastatic outgrowth through the activation of extracellular matrix remodeling, inflammation, migration, angiogenesis, and invasion. We dissect the potential use of new molecules that interfere with the HGF/c-MET axis as therapeutic targets for future clinical trials in cancer disease.

  2. TWEAK/Fn14 axis: a promising target for the treatment of cardiovascular diseases.

    Directory of Open Access Journals (Sweden)

    Luis Miguel Blanco-Colio

    2014-01-01

    Full Text Available Cardiovascular diseases (CVD are the first cause of mortality in Western countries. CVD include several pathologies such as coronary heart disease, stroke or cerebrovascular accident, congestive heart failure, peripheral arterial disease and aortic aneurysm, among others. Interaction between members of the tumor necrosis factor (TNF superfamily and their receptors elicits several biological actions that could participate in CVD. Tumor necrosis factor-like weak inducer of apoptosis (TWEAK and its functional receptor, fibroblast growth factor-inducible molecule 14 (Fn14, are two proteins belonging to the TNF superfamily that activate NF-κB by both canonical and non-canonical pathways and regulate several cell functions such as proliferation, migration, differentiation, cell death, inflammation, and angiogenesis. TWEAK/Fn14 axis plays a beneficial role in tissue repair after acute injury. However, persistent TWEAK/Fn14 activation mediated by blocking experiments or overexpression experiments in animal models has shown an important role of this axis in the pathological remodeling underlying CVD. In this review, we summarize the role of TWEAK/Fn14 pathway in the development of CVD, focusing on atherosclerosis and stroke and the molecular mechanisms by which TWEAK/Fn14 interaction participates in these pathologies. We also review the role of the soluble form of TWEAK as a biomarker for the diagnosis and prognosis of CVD. Finally, we highlight the results obtained with other members of the TNF superfamily that also activate canonical and non-canonical NF-κB pathway.

  3. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  4. The peripheral chromosome scaffold, a novel structural component of mitotic chromosomes.

    Science.gov (United States)

    Sheval, Eugene V; Polyakov, Vladimir Y

    2008-06-01

    Using an original high-salt extraction protocol, we observed a novel chromosome substructure, referred to as the peripheral chromosome scaffold. This chromosome domain contained the perichromosomal layer proteins pKi-67, B23/nucleophosmin and fibrillarin, but no DNA fragments (i.e., the loop domain bases were not associated with the peripheral scaffold). Modern models of chromosome organization do not predict the existence of a peripheral chromosome scaffold domain, and thus our observations have conceptual implications for understanding chromosome architecture. PMID:18337132

  5. A Computational Model for Simulating Spaceflight Induced Bone Remodeling

    Science.gov (United States)

    Pennline, James A.; Mulugeta, Lealem

    2014-01-01

    An overview of an initial development of a model of bone loss due to skeletal unloading in weight bearing sites is presented. The skeletal site chosen for the initial application of the model is the femoral neck region because hip fractures can be debilitating to the overall performance health of astronauts. The paper begins with the motivation for developing such a model of the time course of change in bone in order to understand the mechanism of bone demineralization experienced by astronauts in microgravity, to quantify the health risk, and to establish countermeasures. Following this, a general description of a mathematical formulation of the process of bone remodeling is discussed. Equations governing the rate of change of mineralized bone volume fraction and active osteoclast and osteoblast are illustrated. Some of the physiology of bone remodeling, the theory of how imbalance in remodeling can cause bone loss, and how the model attempts to capture this is discussed. The results of a preliminary validation analysis that was carried out are presented. The analysis compares a set of simulation results against bone loss data from control subjects who participated in two different bed rest studies. Finally, the paper concludes with outlining the current limitations and caveats of the model, and planned future work to enhance the state of the model.

  6. The human tri-peptide GHK and tissue remodeling.

    Science.gov (United States)

    Pickart, Loren

    2008-01-01

    Tissue remodeling follows the initial phase of wound healing and stops inflammatory and scar-forming processes, then restores the normal tissue morphology. The human peptide Gly-(L-His)-(L-Lys) or GHK, has a copper 2+ (Cu(2+)) affinity similar to the copper transport site on albumin and forms GHK-Cu, a complex with Cu(2+). These two molecules activate a plethora of remodeling related processes: (1) chemoattraction of repair cells such as macrophages, mast cells, capillary cells; (2) anti-inflammatory actions (suppression of free radicals, thromboxane formation, release of oxidizing iron, transforming growth factor beta-1, tumor necrosis factor alpha and protein glycation while increasing superoxide dismutase, vessel vasodilation, blocking ultraviolet damage to skin keratinocytes and improving fibroblast recovery after X-ray treatments); (3) increases protein synthesis of collagen, elastin, metalloproteinases, anti-proteases, vascular endothelial growth factor, fibroblast growth factor 2, nerve growth factor, neutrotropins 3 and 4, and erythropoietin; (4) increases the proliferation of fibroblasts and keratinocytes; nerve outgrowth, angiogenesis, and hair follicle size. GHK-Cu stimulates wound healing in numerous models and in humans. Controlled studies on aged skin demonstrated that it tightens skin, improves elasticity and firmness, reduces fine lines, wrinkles, photodamage and hyperpigmentation. GHK-Cu also improves hair transplant success, protects hepatic tissue from tetrachloromethane poisoning, blocks stomach ulcer development, and heals intestinal ulcers and bone tissue. These results are beginning to define the complex biochemical processes that regulate tissue remodeling. PMID:18644225

  7. Remodeling of Kalri Baghar (K.B Feeder

    Directory of Open Access Journals (Sweden)

    ATTA MUHAMMAD PHUL

    2010-10-01

    Full Text Available The shortage of irrigation water supplies and reduced water carrying capacity of Kalri Baghar (K.B feeder require remodeling of the canal (an off-taking canal from right bank of Indus River at Kotri Barrage. The designed normal supply level (NSL capacity of K.B feeder was 257 cumecs (9100 cusecs, but it has now maximum flow rate of 241 cumecs (8500 cusecs due to damaged cross-section and silted normal flow area. In present condition only culturable command area (C.C.A needs 277 cumecs, and the requirement of water supply is additional. The hydraulic parameters are revised up to its potential and remodeled the canal using C++ simulation model based on Lacey?s Method and FlowMaster Model. Using these models present discharge is enhanced 5, 10, and 20%, which revealed changes in hydraulic parameters of the canal. The total length of the canal is 5761 m (18,900 ft in which there is 4% of stone pitching and concrete lining and rest of the channel is passing through sandy loam soil, rocks and coarse sand areas. The regime (stable earthen channel cross-section is remodeled using Lacey?s method. The stone and concrete lined section is redesigned by Manning?s procedure using FlowMaster simulation model. It is required and feasible to modify water carrying capacity of the NSL of the channel by 20% as compared to current conditions.

  8. LIGHT is a crucial mediator of airway remodeling.

    Science.gov (United States)

    Hung, Jen-Yu; Chiang, Shyh-Ren; Tsai, Ming-Ju; Tsai, Ying-Ming; Chong, Inn-Wen; Shieh, Jiunn-Min; Hsu, Ya-Ling

    2015-05-01

    Chronic inflammatory airway diseases like asthma and chronic obstructive pulmonary disease are major health problems globally. Airway epithelial cells play important role in airway remodeling, which is a critical process in the pathogenesis of diseases. This study aimed to demonstrate that LIGHT, an inflammatory factor secreted by T cells after allergen exposure, is responsible for promoting airway remodeling. LIGHT increased primary human bronchial epithelial cells (HBECs) undergoing epithelial-mesenchymal transition (EMT) and expressing MMP-9. The induction of EMT was associated with increased NF-κB activation and p300/NF-κB association. The interaction of NF-κB with p300 facilitated NF-κB acetylation, which in turn, was bound to the promoter of ZEB1, resulting in E-cadherin downregulation. LIGHT also stimulated HBECs to produce numerous cytokines/chemokines that could worsen airway inflammation. Furthermore, LIGHT enhanced HBECs to secrete activin A, which increased bronchial smooth muscle cell (BSMC) migration. In contrast, depletion of activin A decreased such migration. The findings suggest a new molecular determinant of LIGHT-mediated pathogenic changes in HBECs and that the LIGHT-related vicious cycle involving HBECs and BSMCs may be a potential target for the treatment of chronic inflammation airway diseases with airway remodeling. PMID:25251281

  9. Quantitative computed tomography imaging of airway remodeling in severe asthma.

    Science.gov (United States)

    Grenier, Philippe A; Fetita, Catalin I; Brillet, Pierre-Yves

    2016-02-01

    Asthma is a heterogeneous condition and approximately 5-10% of asthmatic subjects have severe disease associated with structure changes of the airways (airway remodeling) that may develop over time or shortly after onset of disease. Quantitative computed tomography (QCT) imaging of the tracheobronchial tree and lung parenchyma has improved during the last 10 years, and has enabled investigators to study the large airway architecture in detail and assess indirectly the small airway structure. In severe asthmatics, morphologic changes in large airways, quantitatively assessed using 2D-3D airway registration and recent algorithms, are characterized by airway wall thickening, luminal narrowing and bronchial stenoses. Extent of expiratory gas trapping, quantitatively assessed using lung densitometry, may be used to assess indirectly small airway remodeling. Investigators have used these quantitative imaging techniques in order to attempt severity grading of asthma, and to identify clusters of asthmatic patients that differ in morphologic and functional characteristics. Although standardization of image analysis procedures needs to be improved, the identification of remodeling pattern in various phenotypes of severe asthma and the ability to relate airway structures to important clinical outcomes should help target treatment more effectively. PMID:26981458

  10. Inflammatory and Bone Remodeling Responses to the Cytolethal Distending Toxins

    Directory of Open Access Journals (Sweden)

    Georgios N. Belibasakis

    2014-04-01

    Full Text Available The cytolethal distending toxins (CDTs are a family of exotoxins produced by a wide range of Gram-negative bacteria. They are known for causing genotoxic stress to the cell, resulting in growth arrest and eventually apoptotic cell death. Nevertheless, there is evidence that CDTs can also perturb the innate immune responses, by regulating inflammatory cytokine production and molecular mediators of bone remodeling in various cell types. These cellular and molecular events may in turn have an effect in enhancing local inflammation in diseases where CDT-producing bacteria are involved, such as Aggregatibacter actinomycetemcomitans, Haemophilus ducreyi, Campylobacter jejuni and Helicobacter hepaticus. One special example is the induction of pathological bone destruction in periodontitis. The opportunistic oral pathogen Aggregatibatcer actinoycemetemcomitans, which is involved in the aggressive form of the disease, can regulate the molecular mechanisms of bone remodeling in a manner that favors bone resorption, with the potential involvement of its CDT. The present review provides an overview of all known to-date inflammatory or bone remodeling responses of CDTs produced by various bacterial species, and discusses their potential contribution to the pathogenesis of the associated diseases.

  11. Remodeling of the methylation landscape in breast cancer metastasis.

    Directory of Open Access Journals (Sweden)

    Marsha Reyngold

    Full Text Available The development of breast cancer metastasis is accompanied by dynamic transcriptome changes and dramatic alterations in nuclear and chromatin structure. The basis of these changes is incompletely understood. The DNA methylome of primary breast cancers contribute to transcriptomic heterogeneity and different metastatic behavior. Therefore we sought to characterize methylome remodeling during regional metastasis. We profiled the DNA methylome and transcriptome of 44 matched primary breast tumors and regional metastases. Striking subtype-specific patterns of metastasis-associated methylome remodeling were observed, which reflected the molecular heterogeneity of breast cancers. These divergent changes occurred primarily in CpG island (CGI-poor areas. Regions of methylome reorganization shared by the subtypes were also observed, and we were able to identify a metastasis-specific methylation signature that was present across the breast cancer subclasses. These alterations also occurred outside of CGIs and promoters, including sequences flanking CGIs and intergenic sequences. Integrated analysis of methylation and gene expression identified genes whose expression correlated with metastasis-specific methylation. Together, these findings significantly enhance our understanding of the epigenetic reorganization that occurs during regional breast cancer metastasis across the major breast cancer subtypes and reveal the nature of methylome remodeling during this process.

  12. Hyperhomocysteinemia promotes vascular remodeling in vein graph in mice.

    Science.gov (United States)

    Tan, Hongmei; Shi, Chengwei; Jiang, Xiaohua; Lavelle, Muriel; Yu, Caijia; Yang, Xiaofeng; Wang, Hong

    2014-01-01

    This study investigated the role and mechanism of Hyperhomocysteinemia (HHcy) on vascular remodeling in mice. We assessed the effect of HHcy on vascular remodeling using a carotid arterial vein patch model in mice with the gene deletion of cystathionine-beta-synthase (Cbs). Vein grafts were harvested 4 weeks after surgery. Cross sections were analyzed using Verhoeff-van Gieson staining, Masson`s Trichrome staining, and immunostaining for morphological analysis and protein level assessment. The effect of Hcy on collagen secretion was examined in cultured rat aortic smooth muscle cells (RASMC). We found that Cbs-/- mice with severe HHcy exhibited thicker neointima and a higher percentage of luminal narrowing in vein grafts. In addition, severe HHcy increased elastin and collagen deposition in the neointima. Further, severe HHcy increases CD45 positive cells and proliferative cells in vein grafts. Finally, Hcy increases collagen secretion in RASMC. These results demonstrate that HHcy increases neointima formation, elastin and collagen deposition following a carotid arterial vein patch. The capacity of Hcy to promote vascular fibrosis and inflammation may contribute to the development of vascular remodeling. PMID:24896329

  13. Pulmonary arterial remodeling revealed by microfocal x-ray tomography

    Science.gov (United States)

    Karau, Kelly L.; Molthen, Robert C.; Johnson, Roger H.; Dhyani, Anita H.; Haworth, Steven T.; Dawson, Christopher A.

    2001-05-01

    Animal models and micro-CT imaging are useful for understanding the functional consequences of, and identifying the genes involved in, the remodeling of vascular structures that accompanies pulmonary vascular disease. Using a micro-CT scanner to image contrast-enhanced arteries in excised lungs from fawn hooded rats (a strain genetically susceptible to hypoxia induced pulmonary hypertension), we found that portions of the pulmonary arterial tree downstream from a given diameter were morphometrically indistinguishable. This 'self-consistency' property provided a means for summarizing the pulmonary arterial tree architecture and mechanical properties using a parameter vector obtained from measurements of the contiguous set of vessel segments comprising the longest (principal) pathway and its branches over a range of vascular pressures. This parameter vector was used to characterize the pulmonary vascular remodeling that occurred in rats exposed to a hypoxic (11.5% oxygen) environment and provided the input to a hemodynamic model relating structure to function. The major effect of the remodeling was a longitudinally (pulmonary artery to arterioles) uniform decrease in vessel distensibility that resulted in a 90% increase in arterial resistance. Despite the almost uniform change in vessel distensibility, over 50% of the resistance increase was attributable to vessels with unstressed diameters less than 125 microns.

  14. Primary Approach to Water (Natural Monopoly) Industry Remodeling

    Institute of Scientific and Technical Information of China (English)

    XiaChengxiang

    2005-01-01

    Natural monopoly, because of its spontaneous or natural characteristics, most have some mysterious causes of reasonableness. Thus, the regulations to its efficiency loss would have a different way compared to other monopolies. That the characteristics of natural monopoly, in the case of water industry, are that the infrastructure investments are very large, most of which are used to build the transportation system? The webs for transporting their products to their customers, and the products are identity goods or services. By examining the characteristics of natural monopoly, this paper proposed a way to break up and remodel the industry of """"""""natural monopoly'. The main clue of remodeling is that the govemments, who represent the public and who ha ve the power to control over public resources, should build and maintain a public web platform for the goods' transportation uses, and break up the barrier of the entry so as to produce a market-oriented competitive structure, The running model and the condition of remodeling are put forward and the cost-revenue analysis of the operation is briefly under consideration.

  15. Age-dependent motor unit remodelling in human limb muscles.

    Science.gov (United States)

    Piasecki, Mathew; Ireland, Alex; Jones, David A; McPhee, Jamie S

    2016-06-01

    Voluntary control of skeletal muscle enables humans to interact with and manipulate the environment. Lower muscle mass, weakness and poor coordination are common complaints in older age and reduce physical capabilities. Attention has focused on ways of maintaining muscle size and strength by exercise, diet or hormone replacement. Without appropriate neural innervation, however, muscle cannot function. Emerging evidence points to a neural basis of muscle loss. Motor unit number estimates indicate that by age around 71 years, healthy older people have around 40 % fewer motor units. The surviving low- and moderate-threshold motor units recruited for moderate intensity contractions are enlarged by around 50 % and show increased fibre density, presumably due to collateral reinnervation of denervated fibres. Motor unit potentials show increased complexity and the stability of neuromuscular junction transmissions is decreased. The available evidence is limited by a lack of longitudinal studies, relatively small sample sizes, a tendency to examine the small peripheral muscles and relatively few investigations into the consequences of motor unit remodelling for muscle size and control of movements in older age. Loss of motor neurons and remodelling of surviving motor units constitutes the major change in ageing muscles and probably contributes to muscle loss and functional impairments. The deterioration and remodelling of motor units likely imposes constraints on the way in which the central nervous system controls movements. PMID:26667009

  16. Variations in atherosclerosis and remodeling patterns in aorta and carotids

    Directory of Open Access Journals (Sweden)

    Fuster Valentin

    2010-03-01

    Full Text Available Abstract Background Atherosclerosis is a progressive disease that causes vascular remodeling that can be positive or negative. The evolution of arterial wall thickening and changes in lumen size under current "standard of care" in different arterial beds is unclear. The purpose of this study was to examine arterial remodeling and progression/regression of atherosclerosis in aorta and carotid arteries of individuals at risk for atherosclerosis normalized over a 1-year period. Methods In this study, 28 patients underwent at least 2 black-blood in vivo cardiovascular magnetic resonance (CMR scans of aorta and carotids over a one-year period (Mean 17.8 ± 7.5 months. Clinical risk profiles for atherosclerosis and medications were documented and patients were followed by their referring physicians under current "standard of care" guidelines. Carotid and aortic wall lumen areas were matched across the time-points from cross-sectional images. Results The wall area increased by 8.67%, 10.64%, and 13.24% per year (carotid artery, thoracic aorta and abdominal aorta respectively, p Conclusions Results of this study of multiple vascular beds indicated that different vascular locations exhibited varying progression of atherosclerosis and remodeling as monitored by CMR.

  17. Galectin-3 inhibition prevents adipose tissue remodelling in obesity.

    Science.gov (United States)

    Martínez-Martínez, E; Calvier, L; Rossignol, P; Rousseau, E; Fernández-Celis, A; Jurado-López, R; Laville, M; Cachofeiro, V; López-Andrés, N

    2016-06-01

    Extracellular matrix remodelling of the adipose tissue has a pivotal role in the pathophysiology of obesity. Galectin-3 (Gal-3) is increased in obesity and mediates inflammation and fibrosis in the cardiovascular system. However, the effects of Gal-3 on adipose tissue remodelling associated with obesity remain unclear. Male Wistar rats were fed either a high-fat diet (33.5% fat) or a standard diet (3.5% fat) for 6 weeks. Half of the animals of each group were treated with the pharmacological inhibitor of Gal-3, modified citrus pectin (MCP; 100 mg kg(-1) per day) in the drinking water. In adipose tissue, obese animals presented an increase in Gal-3 levels that were accompanied by an increase in pericellular collagen. Obese rats exhibited higher adipose tissue inflammation, as well as enhanced differentiation degree of the adipocytes. Treatment with MCP prevented all the above effects. In mature 3T3-L1 adipocytes, Gal-3 (10(-8 )m) treatment increased fibrosis, inflammatory and differentiation markers. In conclusion, Gal-3 emerges as a potential therapeutic target in adipose tissue remodelling associated with obesity and could have an important role in the development of metabolic alterations associated with obesity. PMID:26853916

  18. Ouabain induces cardiac remodeling in rats independent of blood pressure

    Institute of Scientific and Technical Information of China (English)

    Xing JIANG; Yan-ping REN; Zhuo-ren L(U)

    2007-01-01

    Aim: To investigate the ouabain's effects on cardiac remodeling in rats. Methods:Male Sprague-Dawley rats were treated with ouabain. Systolic blood pressure(SBP) was recorded weekly. After 4 and 6 weeks, echocardiography were performed,hemodynamic parameters were measured by invasive cardiac catheterization,changes in cardiac ultrastructure were analyzed using transmission electron microscopy, the collagen fraction of the left ventricle was assessed with Picrosirius red stain, and RT-PCR was applied to evaluate the mRNA level of myosin heavy chain-α and-β in the left ventricle. Results: Having been treated with ouabain for 4 weeks, there was no significant difference in the mean SBP of the two groups.However, left ventricular hypertrophy, myocardial ultrastructure deterioration,and extracellular matrix remodeling were induced by ouabain treatment; meanwhile,cardiac systolic and diastolic performance were both worsened. Moreover, the cardiac MHC-β mRNA was upregulated by ouabain treatment, whereas MHC-αmRNA was downregulated. After 4 weeks, the mean SBP in the ouabain group began to increase and was significantly higher than that in control group after 6 weeks (P<0.01); the rats' cardiac structure and function were worsened.Conclusion: These results suggested that ouabain induces alterations in cardiac structure and function, and the effects happened before the increase of blood pressure. The results indicated that ouabain induced cardiac remodeling in rats independent of blood pressure.

  19. Multi-Axis Accelerometer Calibration System

    Science.gov (United States)

    Finley, Tom; Parker, Peter

    2010-01-01

    A low-cost, portable, and simplified system has been developed that is suitable for in-situ calibration and/or evaluation of multi-axis inertial measurement instruments. This system overcomes facility restrictions and maintains or improves the calibration quality for users of accelerometer-based instruments with applications in avionics, experimental wind tunnel research, and force balance calibration applications. The apparatus quickly and easily positions a multi-axis accelerometer system into a precisely known orientation suitable for in-situ quality checks and calibration. In addition, the system incorporates powerful and sophisticated statistical methods, known as response surface methodology and statistical quality control. These methods improve calibration quality, reduce calibration time, and allow for increased calibration frequency, which enables the monitoring of instrument stability over time.

  20. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    Science.gov (United States)

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  1. Local Pancake Defeats Axis of Evil

    OpenAIRE

    Vale, Chris

    2005-01-01

    Among the biggest surprises revealed by COBE and confirmed by WMAP measurements of the temperature anisotropy of the CMB are the anomalous features in the 2-point angular correlation function on very large angular scales. In particular, the $\\ell = 2$ quadrupole and $\\ell = 3$ octopole terms are surprisingly planar and aligned with one another, which is highly unlikely for a statistically isotropic Gaussian random field, and the axis of the combined low-$\\ell$ signal is perpendicular to eclip...

  2. Parking Strategies for Vertical Axis Wind Turbines

    OpenAIRE

    2012-01-01

    Strategies for parking a vertical axis wind turbine at storm load are considered. It is proposed that if a directly driven permanent magnet synchronous generator is used, an elegant choice is to short-circuit the generator at storm, since this makes the turbine efficiently damped. Nondamped braking is found to be especially problematic for the case of two blades where torsional oscillations may imply thrust force oscillations within a range of frequencies.

  3. Turbulence in vertical axis wind turbine canopies

    OpenAIRE

    Kinzel, Matthias; Araya, Daniel B.; Dabiri, John O.

    2015-01-01

    Experimental results from three different full scale arrays of vertical-axis wind turbines (VAWTs) under natural wind conditions are presented. The wind velocities throughout the turbine arrays are measured using a portable meteorological tower with seven, vertically staggered, three-component ultrasonic anemometers. The power output of each turbine is recorded simultaneously. The comparison between the horizontal and vertical energy transport for the different turbine array sizes shows the i...

  4. Chromosome engineering: power tools for plant genetics.

    Science.gov (United States)

    Chan, Simon W L

    2010-12-01

    The term "chromosome engineering" describes technologies in which chromosomes are manipulated to change their mode of genetic inheritance. This review examines recent innovations in chromosome engineering that promise to greatly increase the efficiency of plant breeding. Haploid Arabidopsis thaliana have been produced by altering the kinetochore protein CENH3, yielding instant homozygous lines. Haploid production will facilitate reverse breeding, a method that downregulates recombination to ensure progeny contain intact parental chromosomes. Another chromosome engineering success is the conversion of meiosis into mitosis, which produces diploid gametes that are clones of the parent plant. This is a key step in apomixis (asexual reproduction through seeds) and could help to preserve hybrid vigor in the future. New homologous recombination methods in plants will potentiate many chromosome engineering applications. PMID:20933291

  5. Radiation induced chromosome instability in human fibroblasts

    International Nuclear Information System (INIS)

    Evidence has been arising that some biological effects can manifest many cell divisions after irradiation. We have demonstrated that de novo chromosome instability can be detected 10- 15 mean population doubling after heavy ion irradiations. This chromosome instability is characterized by end to end fusions between specific chromosomes. The specificity of the instability may differ from one donor to another but for the same donor, the same instability should be observed after irradiation, during the senescence process and after SV40 transfection (before crisis). In irradiated primary culture fibroblasts, the expression of the delayed chromosomal instability lasts for several cell divisions without inducing cell death. Several rounds of fusions- breakage-fusions can be performed and unbalanced clones emerge (gain or loss of chromosomes with the shorter telomeres would become unstable first.. The difference in the chromosomal instability among donors could be due to a polymorphism in telomere lengths. This could induce large variation in long term response to irradiation among individuals. (author)

  6. Endocrine disruptors and estrogenic effects on male reproductive axis

    Institute of Scientific and Technical Information of China (English)

    Suresh C. Sikka; Run Wang

    2008-01-01

    Endocrine disruptors (e.g., polychlorinated biphenyls [PCBs], dichlorodiphenyl-trichloroethane [DDT], dioxin,and some pesticides) are estrogen-like and anti-androgenic chemicals in the environment. They mimic natural hormones,inhibit the action of hormones, or alter the normal regulatory function of the endocrine system and have potential hazardous effects on male reproductive axis causing infertility. Although testicular and prostate cancers, abnormal sexual development, undescended testis, chronic inflammation, Sertoli-cell-only pattern, hypospadias, altered pituitary and thyroid gland functions are also observed, the available data are insufficient to deduce worldwide conclusions.The development of intra-cytoplasmic sperm injection (ICSI) is beyond doubt the most important recent breakthrough in the treatment of male infertility, but it does not necessarily treat the cause and may inadvertently pass on adverse genetic consequences. Many well-controlled clinical studies and basic scientific discoveries in the physiology,biochemistry, and molecular and cellular biology of the male reproductive system have helped in the identification of greater numbers of men with male factor problems. Newer tools for the detection of Y-chromosome deletions have further strengthened the hypothesis that the decline in male reproductive health and fertility may be related to the presence of certain toxic chemicals in the environment. Thus the etiology, diagnosis, and treatment of male factor infertility remain a real challenge. Clinicians should always attempt to identify the etiology of a possible testicular toxicity, assess the degree of risk to the patient being evaluated for infertility, and initiate a plan to control and prevent exposure to others once an association between occupation/toxicant and infertility has been established.

  7. Meiosis I: When Chromosomes Undergo Extreme Makeover

    OpenAIRE

    Miller, Matthew P.; Amon, Angelika; Ünal, Elçin

    2013-01-01

    The ultimate success of cell division relies on the accurate partitioning of the genetic material. Errors in this process occur in nearly all tumors and are the leading cause of miscarriages and congenital birth defects in humans. Two cell divisions, mitosis and meiosis, use common as well as unique mechanisms to ensure faithful chromosome segregation. In mitosis, alternating rounds of DNA replication and chromosome segregation preserves the chromosome complement of the progenitor cell. In co...

  8. Novel Gene Acquisition on Carnivore Y Chromosomes

    OpenAIRE

    Murphy, William J.; A J Pearks Wilkerson; Terje Raudsepp; Richa Agarwala; Schäffer, Alejandro A.; Roscoe Stanyon; Chowdhary, Bhanu P

    2006-01-01

    Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we...

  9. Identification of bacterial cells by chromosomal painting.

    OpenAIRE

    Lanoil, B. D.; Giovannoni, S J

    1997-01-01

    Chromosomal painting is a technique for the microscopic localization of genetic material. It has been applied at the subcellular level to identify regions of eukaryotic chromosomes. Here we describe the development of bacterial chromosomal painting (BCP), a related technology for the identification of bacterial cells. Purified genomic DNAs from six bacterial strains were labeled by nick translation with the fluorochrome Fluor-X, Cy3, or Cy5. The average size of the labeled fragments was ca. 5...

  10. Holoprosencephaly due to Numeric Chromosome Abnormalities

    OpenAIRE

    Solomon, Benjamin D.; Rosenbaum, Kenneth N.; Meck, Jeanne M.; Muenke, Maximilian

    2010-01-01

    Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been ...

  11. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    OpenAIRE

    Daniela Mierla; Viorica Radoi; Veronica Stoian

    2012-01-01

    Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, ka...

  12. How does DNA break during chromosomal translocations?

    OpenAIRE

    Nambiar, Mridula; Raghavan, Sathees C.

    2011-01-01

    Chromosomal translocations are one of the most common types of genetic rearrangements and are molecular signatures for many types of cancers. They are considered as primary causes for cancers, especially lymphoma and leukemia. Although many translocations have been reported in the last four decades, the mechanism by which chromosomes break during a translocation remains largely unknown. In this review, we summarize recent advances made in understanding the molecular mechanism of chromosomal t...

  13. Advances in plant chromosome genomics

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Vrána, Jan; Cápal, Petr; Kubaláková, Marie; Burešová, Veronika; Šimková, Hana

    2014-01-01

    Roč. 32, č. 1 (2014), s. 122-136. ISSN 0734-9750 R&D Projects: GA ČR GAP501/10/1740; GA ČR GAP501/10/1778; GA ČR GBP501/12/G090; GA MŠk(CZ) LO1204 Grant ostatní: GA MŠk(CZ) ED0007/01/01 Institutional support: RVO:61389030 Keywords : BAC library * Chromosome sorting * Cytogenetics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.015, year: 2014

  14. Multiple chromosomes of Azotobacter vinelandii.

    OpenAIRE

    1989-01-01

    The number of copies of the genes leuB, nifH, nifD, and nifK per cell of Azotobacter vinelandii has been determined to be about 80. A beta-lactamase gene was integrated into the A. vinelandii chromosome by single-point crossover. Subsequently, we have been able to detect nearly 80 copies of this beta-lactamase gene per cell of A. vinelandii when cultured for a large number of generations in the presence of ampicillin. The multiple copies of the beta-lactamase gene do not seem to be present on...

  15. Chromosome banding in Amphibia. XXIV. The B chromosomes of Gastrotheca espeletia (Anura, Hylidae).

    Science.gov (United States)

    Schmid, M; Ziegler, C G; Steinlein, C; Nanda, I; Haaf, T

    2002-01-01

    The mitotic chromosomes of an Ecuadorian population of the marsupial frog Gastrotheca espeletia were analyzed by means of banding techniques and fluorescence in situ hybridization. This species is characterized by unusual supernumerary (B) chromosomes. The maximum number of B chromosomes is 9 and they occur in three different morphological types. Banding analyses show that the B chromosomes are completely heterochromatic, consist of AT base pair-rich repeated DNA sequences, replicate their DNA in very late S-phase of the cell cycle, and are probably derived from a centromeric or paracentromeric region of a standard (A) chromosome. Exceptionally, the B chromosomes carry 18S + 28S ribosomal RNA genes and the conserved vertebrate telomeric DNA sequence appears to be underrepresented. Flow cytometric measurements of the nuclear DNA content differentiate between individuals with different numbers of B chromosomes. Significantly more B chromosomes are present in female than in male animals. PMID:12438715

  16. Giemsa C-banding of Barley Chromosomes. IV. Chromosomal Constitution of Autotetraploid Barley

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1984-01-01

    homologues of each of the chromosomes. The aneuploid C2--seedlings were fairly equally distributed on hypo-and hyperploids, and on the seven chromosome groups. This suggests that a particular chromosome is lost or gained at random in gametes and embryos. The 11 C3--seedlings comprised seven true euploids......The progeny of an autotetraploid barley plant (C1) consisted of 45 tetraploids and 33 aneuploids. Giemsa C-banding was used to identify each of the chromosomes in 20 euploid and 31 aneuploid C2--seedlings, and in 11 C3--offspring of aneuploid C2--plants. The euploid C2--seedlings all had four......, one seedling with 2n=28 having an extra chromosome 6 and missing one chromosome 3, and three seedlings with 2n=29. The chromosomal composition of aneuploid C3--seedlings did not reflect that of their aneuploid C2--parents with respect to missing or extra chromosomes. Two hypohexaploid C2--seedlings...

  17. The human urokinase-plasminogen activator gene (PLAU) is located on chromosome 10q24 centromeric to the HOX11 gene

    Energy Technology Data Exchange (ETDEWEB)

    Stein, P.M.; Stass, S.A.; Kagan, J. (Univ. of Texas, Houston (United States))

    1993-04-01

    Urokinase-plasminogen activator is one of two soluble serine proteases that are produced by humans and that convert plasminogen, an inactive proenzyme present in plasma and other extracellular fluids, to plasmin, a protease with broad substrate specificities. Its activity is involved in processes requiring localized extracellular proteolysis such as fibrinolysis, tissue remodeling, and cell migration. Increased production of urokinase has been associated with cancer metastases. The gene for urokinase-plasminogen activator, PLAU, was mapped to chromosome 10q24-qter. By employing somatic cell genetics, polymerase chain reaction (PCR), and Southern blot analysis, the authors assign PLAU to chromosome 10q24. Human chromosome segment 10q23-q25 contains the genes for terminal deoxynucleotidyltransferase, cytochrome P450IIC, glutamic-oxaloacetic transaminase, and plasma retinol binding protein, which form a syntenic group on murine chromosome 19. It is therfore of interest that PLAU and glutamate dehydrogenase, which are on murine chromosome 14, also map in or close to this region of human chromosome 10.

  18. Microtubule detyrosination guides chromosomes during mitosis

    OpenAIRE

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K.; Magiera, Maria M.; Zaytsev, Anatoly V.; Pereira, Ana L.; Janke, Carsten; Grishchuk, Ekaterina L.; Maiato, Helder

    2015-01-01

    Before chromosomes segregate into daughter cells they align at the mitotic spindle equator, a process known as chromosome congression. CENP-E/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically towards the equator. Here we found that congression of pole-proximal c...

  19. Exceptional Complex Chromosomal Rearrangements in Three Generations

    Directory of Open Access Journals (Sweden)

    Hannie Kartapradja

    2015-01-01

    Full Text Available We report an exceptional complex chromosomal rearrangement (CCR found in three individuals in a family that involves 4 chromosomes with 5 breakpoints. The CCR was ascertained in a phenotypically abnormal newborn with additional chromosomal material on the short arm of chromosome 4. Maternal karyotyping indicated that the mother carried an apparently balanced CCR involving chromosomes 4, 6, 11, and 18. Maternal transmission of the derivative chromosome 4 resulted in partial trisomy for chromosomes 6q and 18q and a partial monosomy of chromosome 4p in the proband. Further family studies found that the maternal grandmother carried the same apparently balanced CCR as the proband’s mother, which was confirmed using the whole chromosome painting (WCP FISH. High resolution whole genome microarray analysis of DNA from the proband’s mother found no evidence for copy number imbalance in the vicinity of the CCR translocation breakpoints, or elsewhere in the genome, providing evidence that the mother’s and grandmother’s CCRs were balanced at a molecular level. This structural rearrangement can be categorized as an exceptional CCR due to its complexity and is a rare example of an exceptional CCR being transmitted in balanced and/or unbalanced form across three generations.

  20. Chromosome heteromorphisms in the Japanese, 3

    International Nuclear Information System (INIS)

    The type and frequency of chromosome variants detected by the C-staining method were ascertained in 1,857 individuals residing in Hiroshima. The most frequent heteromorphic variant was the total inversion of the C-band in chromosome 9 found in 27 individuals (1.45%). The total inversion of the C-band in chromosome 1 was not seen in this sample, but the partial inversion of the C-band in chromosome 1 was found in 18 persons (0.97%). Partial inversion was also detected in the C-band in chromosome 9 in 22 individuals (1.18%). In chromosome 16, neither total nor partial inversion of the C-band was observed in the present study. The frequencies of chromosomes 1, 9, and 16 with a very large C-band were 0.70%, 0.22%, and 0.54%, respectively. Aside from these (1, 9, and 16) a very large C-band was found occasionally in chromosomes 4, 5, 6, 11, 12, 14, and 15, and an unusual insertion of the Y chromosome was observed. A total of 128 C-band variants (6.89%) was found in the 1,857 Hiroshima residents. (author)

  1. Cognitive and medical features of chromosomal aneuploidy.

    Science.gov (United States)

    Hutaff-Lee, Christa; Cordeiro, Lisa; Tartaglia, Nicole

    2013-01-01

    This chapter describes the physical characteristics, medical complications, and cognitive and psychological profiles that are associated with chromosomal aneuploidy conditions, a group of conditions in which individuals are born with one or more additional chromosome. Overall, chromosomal aneuploidy conditions occur in approximately 1 in 250 children. Information regarding autosomal disorders including trisomy 21 (Down syndrome), trisomy 13 (Patau syndrome), and trisomy 18 (Edward syndrome) are presented. Sex chromosome aneuploidy conditions such as Klinefelter syndrome (47,XXY), XYY, trisomy X, and Turner syndrome (45,X), in addition to less frequently occurring tetrasomy and pentasomy conditions are also covered. Treatment recommendations and suggestions for future research directions are discussed. PMID:23622175

  2. Chromosomal aberrations in ore miners of Slovakia

    International Nuclear Information System (INIS)

    A pilot study was performed in which the incidence of chromosomal aberrations in lymphocytes of miners in ore mines located in Central Slovakia was monitored and related to lifetime underground radon exposure and to lifetime smoking. The conclusions drawn from the results of the study were as follows: the counts of chromosomal aberrations in lymphocytes of miners were significantly higher than in an age matched control group of white-collar staff; the higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; a dependence of chromosomal aberration counts on the exposure to radon could not be assessed. (A.K.)

  3. Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei.

    Science.gov (United States)

    Stanne, Tara M; Narayanan, Mani Shankar; Ridewood, Sophie; Ling, Alexandra; Witmer, Kathrin; Kushwaha, Manish; Wiesler, Simone; Wickstead, Bill; Wood, Jennifer; Rudenko, Gloria

    2015-11-01

    ISWI chromatin remodelers are highly conserved in eukaryotes and are important for the assembly and spacing of nucleosomes, thereby controlling transcription initiation and elongation. ISWI is typically associated with different subunits, forming specialized complexes with discrete functions. In the unicellular parasite Trypanosoma brucei, which causes African sleeping sickness, TbISWI down-regulates RNA polymerase I (Pol I)-transcribed variant surface glycoprotein (VSG) gene expression sites (ESs), which are monoallelically expressed. Here, we use tandem affinity purification to determine the interacting partners of TbISWI. We identify three proteins that do not show significant homology with known ISWI-associated partners. Surprisingly, one of these is nucleoplasmin-like protein (NLP), which we had previously shown to play a role in ES control. In addition, we identify two novel ISWI partners, regulator of chromosome condensation 1-like protein (RCCP) and phenylalanine/tyrosine-rich protein (FYRP), both containing protein motifs typically found on chromatin proteins. Knockdown of RCCP or FYRP in bloodstream form T. brucei results in derepression of silent variant surface glycoprotein ESs, as had previously been shown for TbISWI and NLP. All four proteins are expressed and interact with each other in both major life cycle stages and show similar distributions at Pol I-transcribed loci. They are also found at Pol II strand switch regions as determined with ChIP. ISWI, NLP, RCCP, and FYRP therefore appear to form a single major ISWI complex in T. brucei (TbIC). This reduced complexity of ISWI regulation and the presence of novel ISWI partners highlights the early divergence of trypanosomes in evolution. PMID:26378228

  4. Chromosomal replicons of higher plants

    Energy Technology Data Exchange (ETDEWEB)

    Van' t Hof, J.

    1987-03-16

    This brief discussion of replicons of higher plants offers a glimpse into the properties of chromosomal DNA replication. It gives evidence that the S phase of unrelated plant species is comprised of temporally ordered replicon families that increase in number with genome size. This orderly process, which assures a normal inheritance of genetic material to recipient daughter cells, is maintained at the level of replicon clusters by two mutually exclusive mechanisms, one involving the rate at which single replicons replicate their allotment of DNA, and another by means of the tempo-pause. The same two mechanisms are used by cells to alter the pattern of chromosomal DNA replication just prior to and during normal development. Both mechanisms are genetically determined and produce genetic effects when disturbed of disrupted by additional non-conforming DNAs. Further insight into how these two mechanisms operate requires more molecular information about the nature of replicons and the factors that govern when a replicon family replicates. Plant material is a rich and ideal source for this information just awaiting exploitation. 63 refs.

  5. Increased chromosome radiosensitivity during pregnancy

    International Nuclear Information System (INIS)

    It was necessary to consider the risks of exposure of pregnant women, not only in relation to the child, but also in relation to their own hypersensitivity. We have demonstrated that pregnancy increases radiosensitivity of chromosome in the mouse at the end of gestation. This is of importance since it may have implications on radioprotection of pregnant women and give experimental guidelines to the problems of hypersensitivity to drugs and cancer aggravation during pregnancy. Blood obtained from women at various times of pregnancy was exposed to ionizing radiations. By comparison to non-pregnant women, an increase in chromosome breakage was observed in metaphases from lymphocytes, after short-term culture in the presence of the serum of the same donor. Immediately after delivery, this increase in radiosensitivity disappeared. In a prospective study, serial analyses showed a very strong correlation between the amount of pregnancy hormones, progesterone in particular, and the increase in radiosensitivity. Pregnant women may have an increased sensitivity to ionizing radiation during the second half of their pregnancy. This study provides the first evidence in human that radiosensitivity may vary in relation to physiological conditions

  6. Retrospective dosimetry by chromosomal analysis

    International Nuclear Information System (INIS)

    The joint EU/CIS project ECP-6, was set up to examine whether cytogenetic dosimetry is possible for persons irradiated years previously at Chernobyl. The paper describes the possibility of achieving this by the examination of blood lymphocytes for unstable and stable chromosome aberrations; dicentrics and translocations. Emphasis was placed on the relatively new fluorescence in situ hybridization (FISH) method for rapid screening for stable translocations. In a collaborative experiment in vitro dose response calibration curves for dicentrics and FISH were produced with gamma radiation over the range 0-1.0 Gy. A pilot study of about 60 liquidators with registered doses ranging from 0-300 mSv was undertaken to determine whether the chromosomal methods may verify the recorded doses. It was concluded that the dicentric is no longer valid as a measured endpoint. Translocations may be used to verify early dosimetry carried out on highly irradiated persons. For the vast majority of lesser exposed subjects FISH is impractical as an individual dosimeter; it may have some value for comparing groups of subjects

  7. Chromosomal instability determines taxane response.

    Science.gov (United States)

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang; Howell, Michael; Ried, Thomas; Habermann, Jens K; Auer, Gert; Brenton, James D; Szallasi, Zoltan; Downward, Julian

    2009-05-26

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells. Overexpression of these "CIN-survival" genes is associated with poor outcome in estrogen receptor-positive breast cancer and occurs frequently in basal-like and Her2-positive cases. In diploid cells, but not in chromosomally unstable cells, paclitaxel causes repression of CIN-survival genes, followed by cell death. In the OV01 ovarian cancer clinical trial, a high level of CIN was associated with taxane resistance but carboplatin sensitivity, indicating that CIN may determine MTS response in vivo. Thus, pretherapeutic assessment of CIN may optimize treatment stratification and clinical trial design using these agents. PMID:19458043

  8. Chromosomal replicons of higher plants

    International Nuclear Information System (INIS)

    This brief discussion of replicons of higher plants offers a glimpse into the properties of chromosomal DNA replication. It gives evidence that the S phase of unrelated plant species is comprised of temporally ordered replicon families that increase in number with genome size. This orderly process, which assures a normal inheritance of genetic material to recipient daughter cells, is maintained at the level of replicon clusters by two mutually exclusive mechanisms, one involving the rate at which single replicons replicate their allotment of DNA, and another by means of the tempo-pause. The same two mechanisms are used by cells to alter the pattern of chromosomal DNA replication just prior to and during normal development. Both mechanisms are genetically determined and produce genetic effects when disturbed of disrupted by additional non-conforming DNAs. Further insight into how these two mechanisms operate requires more molecular information about the nature of replicons and the factors that govern when a replicon family replicates. Plant material is a rich and ideal source for this information just awaiting exploitation. 63 refs

  9. The X chromosome of monotremes shares a highly conserved region with the eutherian and marsupial X chromosomes despite the absence of X chromosome inactivation

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.M.; Spencer, J.A.; Graves, J.A.M. (La Trobe Univ., Bundoora, Victoria (Australia)); Riggs, A.D. (Beckman Inst., Duarte, CA (USA))

    1990-09-01

    Eight genes, located on the long arm of the human X chromosome and present on the marsupial X chromosome, were mapped by in situ hybridization to the chromosomes of the platypus Ornithorhynchus anatinus, one of the three species of monotreme mammals. All were located on the X chromosome. The authors conclude that the long arm of the human X chromosome represents a highly conserved region that formed part of the X chromosome in a mammalian ancestor at least 150 million years ago. Since three of these genes are located on the long arm of the platypus X chromosome, which is G-band homologous to the Y chromosome and apparently exempt from X chromosome inactivation, the conservation of this region has evidently not depended on isolation by X-Y chromosome differentiation and X chromosome inactivation.

  10. Remodeling of the pulmonary circulation - a novel response to allergic airway inflammation

    OpenAIRE

    Rydell-Törmänen, Kristina

    2008-01-01

    Asthma is characterized, not only by inflammation but also by airway and vascular remodeling. Airway remodeling is established early in disease, structural alterations have been found in children, and is thought to contribute to asthma symptoms. Unfortunately, airway remodeling is considered difficult to reverse and it seldom resolves completely. Studies of vascular involvement in asthma have mainly focused on the tracheal and bronchial microcirculation, as these vessels are relatively easy t...

  11. Bronchial smooth muscle remodeling involves calcium-dependent enhanced mitochondrial biogenesis in asthma

    OpenAIRE

    Trian, Thomas; Benard, Giovanni; Begueret, Hugues; Rossignol, Rodrigue; Girodet, Pierre-Olivier; Ghosh, Debajyoti; Ousova, Olga; Vernejoux, Jean-Marc; Marthan, Roger; Tunon-de-Lara, José-Manuel; Berger, Patrick

    2007-01-01

    Asthma and chronic obstructive pulmonary disease (COPD) are characterized by different patterns of airway remodeling, which all include an increased mass of bronchial smooth muscle (BSM). A remaining major question concerns the mechanisms underlying such a remodeling of BSM. Because mitochondria play a major role in both cell proliferation and apoptosis, we hypothesized that mitochondrial activation in BSM could play a role in this remodeling. We describe that both the mitochondrial mass and ...

  12. Postmyocardial Infarct Remodeling and Heart Failure: Potential Contributions from Pro- and Antiaging Factors

    OpenAIRE

    Idikio, Halliday A.

    2011-01-01

    Myocardial infarction and adverse postinfarct remodeling in older persons lead to poor outcome and need greater understanding of the contributions of age-related factors on abnormal cardiac function and management. In this perspective, how normal aging processes could contribute to the events of post-myocardial infarction and remodeling is reviewed. Post-myocardial infarction and remodeling involve cardiomechanical factors and neurohormonal response. Many factors prevent or accelerate aging...

  13. Mechanism of the Susceptibility of Remodeled Pulmonary Vessels to Drug‐Induced Cell Killing

    OpenAIRE

    Ibrahim, Yasmine F.; Wong, Chi‐Ming; Pavlickova, Ludmila; Liu, Lingling; Trasar, Lobsang; Bansal, Geetanjali; Suzuki, Yuichiro J.

    2014-01-01

    Background Pulmonary arterial hypertension remains a devastating disease without a cure. The major complication of this disease is the abnormal growth of vascular cells, resulting in pulmonary vascular remodeling. Thus, agents, which affect the remodeled vessels by killing unwanted cells, should improve treatment strategies. The present study reports that antitumor drugs selectively kill vascular cells in remodeled pulmonary vessels in rat models of pulmonary hypertension. Methods and Results...

  14. Generation and Purification of Human INO80 Chromatin Remodeling Complexes and Subcomplexes

    OpenAIRE

    Chen, Lu; Ooi, Soon-Keat; Conaway, Ronald C.; Conaway, Joan W

    2014-01-01

    INO80 chromatin remodeling complexes regulate nucleosome dynamics and DNA accessibility by catalyzing ATP-dependent nucleosome remodeling. Human INO80 complexes consist of 14 protein subunits including Ino80, a SNF2-like ATPase, which serves both as the catalytic subunit and the scaffold for assembly of the complexes. Functions of the other subunits and the mechanisms by which they contribute to the INO80 complex's chromatin remodeling activity remain poorly understood, in part due to the cha...

  15. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae

    Directory of Open Access Journals (Sweden)

    Artoni Roberto F

    2011-07-01

    Full Text Available Abstract Background The Characidium (a Neotropical fish group have a conserved diploid number (2n = 50, but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR. In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish.

  16. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae)

    Science.gov (United States)

    2011-01-01

    Background The Characidium (a Neotropical fish group) have a conserved diploid number (2n = 50), but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR). In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH) using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish. PMID:21787398

  17. Methamphetamine and the hypothalamic-pituitary-adrenal axis

    OpenAIRE

    Zuloaga, Damian G.; Jacosbskind, Jason S.; Raber, Jacob

    2015-01-01

    Psychostimulants such as methamphetamine (MA) induce significant alterations in the function of the hypothalamic-pituitary-adrenal (HPA) axis. These changes in HPA axis function are associated with altered stress-related behaviors and might contribute to addictive processes such as relapse. In this mini-review we discuss acute and chronic effects of MA (adult and developmental exposure) on the HPA axis, including effects on HPA axis associated genes/proteins, brain regions, and behaviors such...

  18. Hypothyroidism and its rapid correction alter cardiac remodeling.

    Directory of Open Access Journals (Sweden)

    Georges Hajje

    Full Text Available The cardiovascular effects of mild and overt thyroid disease include a vast array of pathological changes. As well, thyroid replacement therapy has been suggested for preserving cardiac function. However, the influence of thyroid hormones on cardiac remodeling has not been thoroughly investigated at the molecular and cellular levels. The purpose of this paper is to study the effect of hypothyroidism and thyroid replacement therapy on cardiac alterations. Thirty Wistar rats were divided into 2 groups: a control (n = 10 group and a group treated with 6-propyl-2-thiouracil (PTU (n = 20 to induce hypothyroidism. Ten of the 20 rats in the PTU group were then treated with L-thyroxine to quickly re-establish euthyroidism. The serum levels of inflammatory markers, such as C-reactive protein (CRP, tumor necrosis factor alpha (TNF-α, interleukin 6 (IL6 and pro-fibrotic transforming growth factor beta 1 (TGF-β1, were significantly increased in hypothyroid rats; elevations in cardiac stress markers, brain natriuretic peptide (BNP and cardiac troponin T (cTnT were also noted. The expressions of cardiac remodeling genes were induced in hypothyroid rats in parallel with the development of fibrosis, and a decline in cardiac function with chamber dilation was measured by echocardiography. Rapidly reversing the hypothyroidism and restoring the euthyroid state improved cardiac function with a decrease in the levels of cardiac remodeling markers. However, this change further increased the levels of inflammatory and fibrotic markers in the plasma and heart and led to myocardial cellular infiltration. In conclusion, we showed that hypothyroidism is related to cardiac function decline, fibrosis and inflammation; most importantly, the rapid correction of hypothyroidism led to cardiac injuries. Our results might offer new insights for the management of hypothyroidism-induced heart disease.

  19. Phosphodiesterase 10A upregulation contributes to pulmonary vascular remodeling.

    Science.gov (United States)

    Tian, Xia; Vroom, Christina; Ghofrani, Hossein Ardeschir; Weissmann, Norbert; Bieniek, Ewa; Grimminger, Friedrich; Seeger, Werner; Schermuly, Ralph Theo; Pullamsetti, Soni Savai

    2011-01-01

    Phosphodiesterases (PDEs) modulate the cellular proliferation involved in the pathophysiology of pulmonary hypertension (PH) by hydrolyzing cAMP and cGMP. The present study was designed to determine whether any of the recently identified PDEs (PDE7-PDE11) contribute to progressive pulmonary vascular remodeling in PH. All in vitro experiments were performed with lung tissue or pulmonary arterial smooth muscle cells (PASMCs) obtained from control rats or monocrotaline (MCT)-induced pulmonary hypertensive (MCT-PH) rats, and we examined the effects of the PDE10 inhibitor papaverine (Pap) and specific small interfering RNA (siRNA). In addition, papaverine was administrated to MCT-induced PH rats from day 21 to day 35 by continuous intravenous infusion to examine the in vivo effects of PDE10A inhibition. We found that PDE10A was predominantly present in the lung vasculature, and the mRNA, protein, and activity levels of PDE10A were all significantly increased in MCT PASMCs compared with control PASMCs. Papaverine and PDE10A siRNA induced an accumulation of intracellular cAMP, activated cAMP response element binding protein and attenuated PASMC proliferation. Intravenous infusion of papaverine in MCT-PH rats resulted in a 40%-50% attenuation of the effects on pulmonary hypertensive hemodynamic parameters and pulmonary vascular remodeling. The present study is the first to demonstrate a central role of PDE10A in progressive pulmonary vascular remodeling, and the results suggest a novel therapeutic approach for the treatment of PH. PMID:21494592

  20. Horizontal axis Levitron—a physics demonstration

    Science.gov (United States)

    Michaelis, Max M.

    2014-01-01

    After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the ‘spignet’. Precession is fundamental to nuclear magnetic resonance, magnetic resonance imaging, particle traps and the movement of bodies in space. Longitudinal and lateral bounce behaviour is explained via ‘the principle of gentle superposition’ of two traps: the micro-precessional and the macro-trap. Theory is initiated. Scaling experiments are mentioned. Industrial applications might follow. Patent pending.

  1. A Portable Single Axis Magnetic Gradiometer

    DEFF Research Database (Denmark)

    Merayo, José M.G.; Petersen, Jan Raagaard; Nielsen, Otto V;

    2001-01-01

    The single axis magnetic gradiometer based on two compact detector compensation (CDC) fluxgate ringcore sensors separated 20 cm is described. Despite its high stability and precision better than 1 nT, the calibration procedures are not straightforward. Firstly, the mono-axial measurement does...... not provide vector information about the magnetic field. Secondly, one of the sensors measures the ambient magnetic field and is used to compensate for the main field at both sensors. Several methods have been developed for characterization of the 2 gradiometer, and the calibration of the gradient...

  2. Pulsed 3-Axis Vector SERF Magnetometer

    Science.gov (United States)

    Hedges, Morgan; Romalis, Michael

    2016-05-01

    We demonstrate a 3-axis atomic vector magnetometer operating in the SERF regime, using a single beam path, and capable of operating in Earth's field using field feedback. It has similar sensitivity along all 3 axes that is fundamentally limited by photon and atom shot noise. The scheme uses a high intensity pump pulse to polarize Rb atoms in ~ 1 μs and a sequence of magnetic field pulses applied while the atoms are monitored during free precession. The sequence used provides minimal sensitivity to pulse errors, while also allowing unambiguous discrimination between external magnetic fields and misalignment between laser and magnetic coil axes.

  3. Optimisation of vertical axis wind turbines

    OpenAIRE

    Roynarin, Wirachai

    2004-01-01

    A practical Vertical Axis Wind Turbine (VAWTs) based on a Darrieus rotor has been designed and tested and found to be capable of self-starting at wind speeds above 4m/s. The self-start feature has been achieved by replacing the usual symmetrical aerofoil blade in the VAWT rotor and by using a concentric Savonius rotor or semi-cylinder turbine. A computer program was produced to compute the power coefficient versus tip speed ratio characteristics of a selected aerofoil profile employed in a VA...

  4. Equilibrium calculations for helical axis stellarators

    International Nuclear Information System (INIS)

    An average method based on a vacuum flux coordinate system is presented. This average method permits the study of helical axis stellarators with toroidally dominated shifts. An ordering is introduced, and to lowest order the toroidally averaged equilibrium equations are reduced to a Grad-Shafranov equation. Also, to lowest order, a Poisson-type equation is obtained for the toroidally varying corrections to the equilibium. By including these corrections, systems that are toroidally dominated, but with significant helical distortion to the equilibrium, may be studied. Numerical solutions of the average method equations are shown to agree well with three-dimensional calculations

  5. Left atrium remodeling after acute myocardial infarction (results of the GISSI-3 Echo Substudy).

    Science.gov (United States)

    Popescu, Bogdan A; Macor, Franco; Antonini-Canterin, Francesco; Giannuzzi, Pantaleo; Temporelli, Pier L; Bosimini, Enzo; Gentile, Francesco; Maggioni, Aldo P; Tavazzi, Luigi; Piazza, Rita; Ascione, Luigi; Stoian, Ioana; Cervesato, Eugenio; Nicolosi, Gian L

    2004-05-01

    To evaluate the existence, timing, and determinants of post-infarction left atrial remodeling, we studied a subgroup of 514 patients from the Third Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico Echo Substudy who underwent 4 serial 2-dimensional echocardiograms up to 6 months after acute myocardial infarction. This study is the first to demonstrate, in a large series of patients, the existence of early and late left atrial remodeling after low-risk acute myocardial infarction and the relation of left atrial remodeling to left ventricular remodeling. PMID:15110211

  6. ATP-Dependent Chromatin Remodeling Factors and Their Roles in Affecting Nucleosome Fiber Composition

    Directory of Open Access Journals (Sweden)

    Alexandra Lusser

    2011-10-01

    Full Text Available ATP-dependent chromatin remodeling factors of the SNF2 family are key components of the cellular machineries that shape and regulate chromatin structure and function. Members of this group of proteins have broad and heterogeneous functions ranging from controlling gene activity, facilitating DNA damage repair, promoting homologous recombination to maintaining genomic stability. Several chromatin remodeling factors are critical components of nucleosome assembly processes, and recent reports have identified specific functions of distinct chromatin remodeling factors in the assembly of variant histones into chromatin. In this review we will discuss the specific roles of ATP-dependent chromatin remodeling factors in determining nucleosome composition and, thus, chromatin fiber properties.

  7. Experimental study on remodeling strength of granular materials under different loads and lengths of time

    Institute of Scientific and Technical Information of China (English)

    韩流; 周伟; 才庆祥; 舒继森; 靖洪文; 李鑫

    2015-01-01

    Remodeled clay and sand rock specimens were prepared by designing lateral confinement and water drainage experiments based on the stress exerted on granular materials in a waste dump. An in situ test was conducted in an internal waste dump; the physical and mechanical parameters of the remodeled rock mass dumped at different time and depths were measured. Based on statistics, regression analysis was performed with regard to the shearing stress parameters acquired from the two tests. Other factors, such as remodeling pressure (burial depth), remodeling time (amount of time since waste was dumped), and the corresponding functional relationship, were determined. Analysis indicates that the cohesion of the remodeled clay and its remodeling pressure are correlated by a quadratic function but are not correlated with remodeling time length. In situ experimental results indicate that the shear strength of reshaped granular materials in the internal dump is positively correlated with burial depth but poorly correlated with time length. CohesionC and burial depthH follow a quadratic function, specifically for a short time since waste has been dumped. As revealed by both in situ and laboratory experiments, the remodeling strength of granular materials varies in a certain pattern. The consistency of such materials verifies the reliability of the remodeling experimental program.

  8. RosettaRemodel: a generalized framework for flexible backbone protein design.

    Directory of Open Access Journals (Sweden)

    Po-Ssu Huang

    Full Text Available We describe RosettaRemodel, a generalized framework for flexible protein design that provides a versatile and convenient interface to the Rosetta modeling suite. RosettaRemodel employs a unified interface, called a blueprint, which allows detailed control over many aspects of flexible backbone protein design calculations. RosettaRemodel allows the construction and elaboration of customized protocols for a wide range of design problems ranging from loop insertion and deletion, disulfide engineering, domain assembly, loop remodeling, motif grafting, symmetrical units, to de novo structure modeling.

  9. Single-axis gyroscopic motion with uncertain angular velocity about spin axis

    Science.gov (United States)

    Singh, S. N.

    1977-01-01

    A differential game approach is presented for studying the response of a gyro by treating the controlled angular velocity about the input axis as the evader, and the bounded but uncertain angular velocity about the spin axis as the pursuer. When the uncertain angular velocity about the spin axis desires to force the gyro to saturation a differential game problem with two terminal surfaces results, whereas when the evader desires to attain the equilibrium state the usual game with single terminal manifold arises. A barrier, delineating the capture zone (CZ) in which the gyro can attain saturation and the escape zone (EZ) in which the evader avoids saturation is obtained. The CZ is further delineated into two subregions such that the states in each subregion can be forced on a definite target manifold. The application of the game theoretic approach to Control Moment Gyro is briefly discussed.

  10. Expression of RANKL/OPG during bone remodeling in vivo

    International Nuclear Information System (INIS)

    Highlights: → This is the first study to determine the relationship between osteogenic differentiation and RANKL/OPG expression during bone remodeling in vivo. → The OPG expression peak occurred during the bone formation phase, whereas the marked elevation of RANKL expression was observed during the bone resorption phase. → Histological analysis showed that RANKL/OPG immunoreactivity was predominantly associated with bone marrow cells in the marrow cavity. → The present study confirmed that RANKL/OPG are key factors linking bone formation to resorption during the bone remodeling process. -- Abstract: The interaction between receptor activator of nuclear factor κB ligand (RANKL) and osteoprotegerin (OPG) plays a dominant role in osteoclastogenesis. As both proteins are produced by osteoblast lineage cells, they are considered to represent a key link between bone formation and resorption. In this study, we investigated the expression of RANKL and OPG during bone remodeling in vivo to determine the relationship between osteoclastogenic stimulation and osteoblastic differentiation. Total RNA was prepared from rat femurs after marrow ablation on days 0, 3, 6, and 9. The temporal activation patterns of osteoblast-related genes (procollagen α1 (I), alkaline phosphatase, osteopontin, and osteocalcin) were examined by Northern blot analysis. An appreciable increase in the expression of these osteoblast markers was observed on day 3. The peak increase in gene expression was observed on day 6 followed by a slight reduction by day 9. Real-time PCR analysis showed that the OPG mRNA expression was markedly upregulated on day 6 and slightly decreased on day 9. In contrast, RANKL mRNA expression was increased by more than 20-fold on day 9. The RANKL/OPG ratio, an index of osteoclastogenic stimulation, peaked on day 9. Histological analysis showed that RANKL and OPG immunoreactivity were predominantly associated with bone marrow cells. The expression of bone formation

  11. Microcirculatory remodeling in marginal zone of duodenal ulcer after bleeding

    Directory of Open Access Journals (Sweden)

    Sulayeva О.N.

    2009-01-01

    Full Text Available To estimate objectively vessels network remodeling in duodenal mucosa after ulcer bleeding the morphometric analysis of marginal ulcer zone biopsies was performed in 32 patients. It was shown that reparation is accompanied with chronic inflammation and acute alteration of microcirculation. Injection hemostasis led to enhancement of microcirculation, development of edema and ischemic alteration of mucosal tissues. Acute neutrophilic infiltration during 1 day was changed on 3 day with granular tissue development and angiogenesis stimulation. Intensification and prolongation of angiogenesis paral-leled with lymphocytes infiltration after 7 days resulted to villi dysmorphogenesis and changes in cellular content of intestinal epithelium.

  12. Intestinal remodelling in mink fed with reduced protein content

    DEFF Research Database (Denmark)

    Chen, Pengmin; Zhao, Jingbo; Nielsen, Vivi Hunnicke;

    2009-01-01

    Low protein intake occurs in humans in relation to diseases, starvation and post-operatively. Low-protein diets may affect the gastrointestinal structure and mechanical function. The aim was to study the passive biomechanical properties and tissue remodelling of the intestine in minks on reduced...... images of the intestinal segments at pre-selected pressures, no-load and zero-stress states, respectively. Circumferential and longitudinal stresses (force per area) and strains (deformation) were computed. The layer thickness was measured from intestinal histological images. No difference in body weight...

  13. REMOD: a computational tool for remodeling neuronal dendrites

    Directory of Open Access Journals (Sweden)

    Panagiotis Bozelos

    2014-05-01

    Full Text Available In recent years, several modeling studies have indicated that dendritic morphology is a key determinant of how individual neurons acquire a unique signal processing profile. The highly branched dendritic structure that originates from the cell body, explores the surrounding 3D space in a fractal-like manner, until it reaches a certain amount of complexity. Its shape undergoes significant alterations not only in various neuropathological conditions, but in physiological, too. Yet, despite the profound effect that these alterations can have on neuronal function, the causal relationship between structure and function remains largely elusive. The lack of a systematic approach for remodeling neuronal cells and their dendritic trees is a key limitation that contributes to this problem. In this context, we developed a computational tool that allows the remodeling of any type of neurons, given a set of exemplar morphologies. The tool is written in Python and provides a simple GUI that guides the user through various options to manipulate selected neuronal morphologies. It provides the ability to load one or more morphology files (.swc or .hoc and choose specific dendrites to operate one of the following actions: shrink, remove, extend or branch (as shown in Figure 1. The user retains complete control over the extent of each alteration and if a chosen action is not possible due to pre-existing structural constraints, appropriate warnings are produced. Importantly, the tool can also be used to extract morphology statistics for one or multiple morphologies, including features such as the total dendritic length, path length to the root, branch order, diameter tapering, etc. Finally, an experimental utility enables the user to remodel entire dendritic trees based on preloaded statistics from a database of cell-type specific neuronal morphologies. To our knowledge, this is the first tool that allows (a the remodeling of existing –as opposed to the de novo

  14. Development of Bone Remodeling Model for Spaceflight Bone Physiology Analysis

    Science.gov (United States)

    Pennline, James A.; Werner, Christopher R.; Lewandowski, Beth; Thompson, Bill; Sibonga, Jean; Mulugeta, Lealem

    2015-01-01

    Current spaceflight exercise countermeasures do not eliminate bone loss. Astronauts lose bone mass at a rate of 1-2% a month (Lang et al. 2004, Buckey 2006, LeBlanc et al. 2007). This may lead to early onset osteoporosis and place the astronauts at greater risk of fracture later in their lives. NASA seeks to improve understanding of the mechanisms of bone remodeling and demineralization in 1g in order to appropriately quantify long term risks to astronauts and improve countermeasures. NASA's Digital Astronaut Project (DAP) is working with NASA's bone discipline to develop a validated computational model to augment research efforts aimed at achieving this goal.

  15. Non-disjunction of chromosome 13

    DEFF Research Database (Denmark)

    Bugge, Merete; Collins, Andrew; Hertz, Jens Michael;

    2007-01-01

    recombination in both maternal MI and MII errors and the former is associated with a significant number of tetrads (33%) that are nullichiasmate, which do not appear to be a feature of normal chromosome 13 meiosis. This study supports the evidence for subtle chromosome-specific influences on the mechanisms that...

  16. Chromosome number9 specific repetitive DNA sequence

    International Nuclear Information System (INIS)

    Human repetitive DNA libraries have been constructed and various recombinant DNA clones isolated that are likely candidates for chromosome specific sequences. The first clone tested (pHuR 98; plasmid human repeat 98) was biotinylated and hybridized to human chromosomes in situ. The hybridized recombinant probe was detected with fluoresceinated avidin, and chromosomes were counter-stained with either propidium iodide or distamycin-DAPI. Specific hybridization to chromosome band 9q1 was obtained. The localization was confirmed by hybridizing radiolabeled pHuR 98 DNA to human chromosomes sorted by flow cytometry. Various methods, including orthogonal field pulsed gel electrophoresis analysis indicate that 75 kilobase blocks of this sequence are interspersed with other repetitive DNA sequences in this chromosome band. This study is the first to report a human repetitive DNA sequence uniquely localized to a specific chromosome. This clone provides an easily detected and highly specific chromosomal marker for molecular cytogenetic analyses in numerous basic research and clinical studies

  17. Chromosomal characterization of Pseudonannolene strinatii (Spirostreptida, Pseudonannolenidae

    Directory of Open Access Journals (Sweden)

    Kleber Agari Campos

    2004-03-01

    Full Text Available The chromosomes of the cave millipede Pseudonannolene strinatii Mauriès, 1974 were investigated. The diploid chromosome number was found to be 2n=16, XX/XY; the C-banding technique revealed a large amount of heterochromatin while the silver staining technique (Ag-NOR evidenced the presence of heteromorphism of the NORs in some cells.

  18. Chromosomal Aneuploidies and Early Embryonic Developmental Arrest

    Directory of Open Access Journals (Sweden)

    Maria Maurer

    2015-07-01

    Full Text Available Background: Selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (IVF technology. The high rate of embryonic developmental arrest during IVF treatment is one of the limitations in achieving this goal. Chromosomal abnormalities are possibly linked with chromosomal arrest and selection against abnormal fertilization products. The objective of this study was to evaluate the frequency and type of chromosomal abnormalities in preimplantation embryos with developmental arrest. Materials and Methods: This cohort study included blastomeres of embryos with early developmental arrest that were biopsied and analyzed by fluorescence in-situ hybridization (FISH with probes for chromosomes 13, 16, 18, 21 and 22. Forty-five couples undergoing IVF treatment were included, and 119 arrested embryos were biopsied. All probes were obtained from the Kinderwunsch Zentrum, Linz, Austria, between August 2009 and August 2011. Results: Of these embryos, 31.6% were normal for all chromosomes tested, and 68.4% were abnormal. Eleven embryos were uniformly aneuploid, 20 were polyploid, 3 were haploid, 11 displayed mosaicism and 22 embryos exhibited chaotic chromosomal complement. Conclusion: Nearly 70% of arrested embryos exhibit chromosomal errors, making chromosomal abnormalities a major cause of embryonic arrest and may be a further explanation for the high developmental failure rates during culture of the embryos in the IVF setting.

  19. Mechanisms of Chromosome Number Evolution in Yeast

    Science.gov (United States)

    Gordon, Jonathan L.; Byrne, Kevin P.; Wolfe, Kenneth H.

    2011-01-01

    The whole-genome duplication (WGD) that occurred during yeast evolution changed the basal number of chromosomes from 8 to 16. However, the number of chromosomes in post-WGD species now ranges between 10 and 16, and the number in non-WGD species (Zygosaccharomyces, Kluyveromyces, Lachancea, and Ashbya) ranges between 6 and 8. To study the mechanism by which chromosome number changes, we traced the ancestry of centromeres and telomeres in each species. We observe only two mechanisms by which the number of chromosomes has decreased, as indicated by the loss of a centromere. The most frequent mechanism, seen 8 times, is telomere-to-telomere fusion between two chromosomes with the concomitant death of one centromere. The other mechanism, seen once, involves the breakage of a chromosome at its centromere, followed by the fusion of the two arms to the telomeres of two other chromosomes. The only mechanism by which chromosome number has increased in these species is WGD. Translocations and inversions have cycled telomere locations, internalizing some previously telomeric genes and creating novel telomeric locations. Comparison of centromere structures shows that the length of the CDEII region is variable between species but uniform within species. We trace the complete rearrangement history of the Lachancea kluyveri genome since its common ancestor with Saccharomyces and propose that its exceptionally low level of rearrangement is a consequence of the loss of the non-homologous end joining (NHEJ) DNA repair pathway in this species. PMID:21811419

  20. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes. PMID:27263828

  1. Physical map of the Bacillus cereus chromosome.

    OpenAIRE

    Kolstø, A B; Grønstad, A; Oppegaard, H

    1990-01-01

    A physical map of the Bacillus cereus chromosome has been constructed by aligning 11 NotI fragments, ranging in size from 200 to 1,300 kilobases. The size of the chromosome is about 5.7 megabases. This is the first Bacillus genome of which a complete physical map has been described.

  2. Compositions for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1998-01-01

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyses. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acid probes are typically of a complexity greater than 50 kb, the complexity depending upon the cytogenetic application. Methods are provided to disable the hybridization capacity of shared, high copy repetitive sequences and/or remove such sequences to provide for useful contrast. Still further methods are provided to produce chromosome-specific staining reagents which are made specific to the targeted chromosomal material, which can be one or more whole chromosomes, one or more regions on one or more chromosomes, subsets of chromosomes and/or the entire genome. Probes and test kits are provided for use in tumor cytogenetics, in the detection of disease related loci, in analysis of structural abnormalities, such as translocations, and for biological dosimetry. Further, methods and prenatal test kits are provided to stain targeted chromosomal material of fetal cells, including fetal cells obtained from maternal blood. Still further, the invention provides for automated means to detect and analyse chromosomal abnormalities.

  3. Mapping of human chromosomal regions related to neoplasia: evidence from chromosomes 1 and 17

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J.D.

    1977-12-01

    In clonal aberrations leading to an excess or partial excess of chromosome I, trisomy for bands 1q25-1q32 was noted in the myeloid cells from all of 34 patients who had various disorders such as acute leukemia, polycythemia vera, and myelofibrosis. This was not the result of a particularly fragile site in that region of the chromosome because the break points in reciprocal translocations that involve it occurred almost exclusively in the short arm. Two consistent rearrangements that have been observed in chromosome 17 produced either duplication of the entire long arm or a translocation of the distal portion of the long arm to chromosome 15. The nonrandom chromosomal changes found in hematologic disorders can now be correlated with the gene loci on these chromosomes or chromosomal segments. Seventy-five genes related to various metabolic enzymes have been mapped; it may be significant that chromosomes carrying gene loci related to nucleic acid metabolism are more frequently involved in hematologic disorders (and other malignancies as well) than are gene loci related to intermediary or carbohydrate metabolism. Furthermore, the known virus-human chromosome associations are closely correlated with the chromosomes affected in hematologic disorders. If one of the effects of carcinogens (including viruses) is to activate genes that regulate host cell DNA synthesis, and if translocations or duplications of specific chromosomal segments produce the same effect, then either of these mechanisms might provide the affected cell with a proliferative advantage.

  4. Review of the Y chromosome and hypertension

    Directory of Open Access Journals (Sweden)

    D. Ely

    2000-06-01

    Full Text Available The Y chromosome from spontaneously hypertensive rats (SHR has a locus that raises blood pressure 20-25 mmHg. Associated with the SHR Y chromosome effect is a 4-week earlier pubertal rise of testosterone and dependence upon the androgen receptor for the full blood pressure effect. Several indices of enhanced sympathetic nervous system (SNS activity are also associated with the SHR Y chromosome. Blockade of SNS outflow reduced the blood pressure effect. Salt sensitivity was increased by the Y chromosome as was salt appetite which was SNS dependent. A strong correlation (r = 0.57, P<0.001 was demonstrable between plasma testosterone and angiotensin II. Coronary collagen increased with blood pressure and the presence of the SHR Y chromosome. A promising candidate gene for the Y effect is the Sry locus (testis determining factor, a transcription factor which may also have other functions.

  5. Genetic conflict and sex chromosome evolution

    Science.gov (United States)

    Meiklejohn, Colin D; Tao, Yun

    2009-01-01

    Chromosomal sex determination systems create the opportunity for the evolution of selfish genetic elements that increase the transmission of one sex chromosome at the expense of its homolog. Because such selfish elements on sex chromosomes can reduce fertility and distort the sex ratio of progeny, unlinked suppressors are expected to evolve, bringing different regions of the genome into conflict over the meiotic transmission of the sex chromosomes. Here we argue that recurrent genetic conflict over sex chromosome transmission is an important evolutionary force that has shaped a wide range of seemingly disparate phenomena including the epigenetic regulation of genes expressed in the germline, the distribution of genes in the genome, and the evolution of hybrid sterility between species. PMID:19931208

  6. Advances in understanding paternally transmitted Chromosomal Abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, F; Sloter, E; Wyrobek, A J

    2001-03-01

    Multicolor FISH has been adapted for detecting the major types of chromosomal abnormalities in human sperm including aneuploidies for clinically-relevant chromosomes, chromosomal aberrations including breaks and rearrangements, and other numerical abnormalities. The various sperm FISH assays have been used to evaluate healthy men, men of advanced age, and men who have received mutagenic cancer therapy. The mouse has also been used as a model to investigate the mechanism of paternally transmitted genetic damage. Sperm FISH for the mouse has been used to detect chromosomally abnormal mouse sperm, while the PAINT/DAPI analysis of mouse zygotes has been used to evaluate the types of chromosomal defects that can be paternally transmitted to the embryo and their effects on embryonic development.

  7. New Y chromosomes and early stages of sex chromosome differentiation: sex determination in Megaselia

    Indian Academy of Sciences (India)

    Walther Traut

    2010-09-01

    The phorid fly Megaselia scalaris is a laboratory model for the turnover and early differentiation of sex chromosomes. Isolates from the field have an XY sex-determining mechanism with chromosome pair 2 acting as X and Y chromosomes. The sex chromosomes are homomorphic but display early signs of sex chromosome differentiation: a low level of molecular differences between X and Y. The male-determining function $(M)$, maps to the distal part of the Y chromosome’s short arm. In laboratory cultures, new Y chromosomes with no signs of a molecular differentiation arise at a low rate, probably by transposition of to these chromosomes. Downstream of the primary signal, the homologue of the Drosophila doublesex (dsx) is part of the sex-determining pathway while Sex-lethal (Sxl), though structurally conserved, is not.

  8. Y-chromosome evolution: emerging insights into processes of Y-chromosome degeneration.

    Science.gov (United States)

    Bachtrog, Doris

    2013-02-01

    The human Y chromosome is intriguing not only because it harbours the master-switch gene that determines gender but also because of its unusual evolutionary history. The Y chromosome evolved from an autosome, and its evolution has been characterized by massive gene decay. Recent whole-genome and transcriptome analyses of Y chromosomes in humans and other primates, in Drosophila species and in plants have shed light on the current gene content of the Y chromosome, its origins and its long-term fate. Furthermore, comparative analysis of young and old Y chromosomes has given further insights into the evolutionary and molecular forces triggering Y-chromosome degeneration and into the evolutionary destiny of the Y chromosome. PMID:23329112

  9. VERITAS: Versatile Triple-Axis Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Il

    2006-04-15

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, {approx} 5 m Curved Guide, {approx} 26 m w/ R 1500 m Straight Guide before the Instrument, {approx} 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world.

  10. VERITAS: Versatile Triple-Axis Spectrometer

    International Nuclear Information System (INIS)

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, ∼ 5 m Curved Guide, ∼ 26 m w/ R 1500 m Straight Guide before the Instrument, ∼ 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world

  11. Novel gene acquisition on carnivore Y chromosomes.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we used direct cDNA selection to isolate and evaluate the extent of novel Y chromosome gene acquisition in the genome of the domestic cat, a species from a different mammalian superorder than human, chimpanzee, and mouse (currently being sequenced. We discovered four novel Y chromosome genes that do not have functional copies in the finished human male-specific region of the Y or on other mammalian Y chromosomes explored thus far. Two genes are derived from putative autosomal progenitors, and the other two have X chromosome homologs from different evolutionary strata. All four genes were shown to be multicopy and expressed predominantly or exclusively in testes, suggesting that their duplication and specialization for testis function were selected for because they enhance spermatogenesis. Two of these genes have testis-expressed, Y-borne copies in the dog genome as well. The absence of the four newly described genes on other characterized mammalian Y chromosomes demonstrates the gene novelty on this chromosome between mammalian orders, suggesting it harbors many lineage-specific genes that may go undetected by traditional comparative genomic approaches. Specific plans to identify the male-specific genes encoded in the Y chromosome of mammals should be a priority.

  12. Chromosome differentiation patterns during cichlid fish evolution

    Directory of Open Access Journals (Sweden)

    Nirchio Mauro

    2010-06-01

    Full Text Available Abstract Background Cichlid fishes have been the subject of increasing scientific interest because of their rapid adaptive radiation which has led to an extensive ecological diversity and their enormous importance to tropical and subtropical aquaculture. To increase our understanding of chromosome evolution among cichlid species, karyotypes of one Asian, 22 African, and 30 South American cichlid species were investigated, and chromosomal data of the family was reviewed. Results Although there is extensive variation in the karyotypes of cichlid fishes (from 2n = 32 to 2n = 60 chromosomes, the modal chromosome number for South American species was 2n = 48 and the modal number for the African ones was 2n = 44. The only Asian species analyzed, Etroplus maculatus, was observed to have 46 chromosomes. The presence of one or two macro B chromosomes was detected in two African species. The cytogenetic mapping of 18S ribosomal RNA (18S rRNA gene revealed a variable number of clusters among species varying from two to six. Conclusions The karyotype diversification of cichlids seems to have occurred through several chromosomal rearrangements involving fissions, fusions and inversions. It was possible to identify karyotype markers for the subfamilies Pseudocrenilabrinae (African and Cichlinae (American. The karyotype analyses did not clarify the phylogenetic relationship among the Cichlinae tribes. On the other hand, the two major groups of Pseudocrenilabrinae (tilapiine and haplochromine were clearly discriminated based on the characteristics of their karyotypes. The cytogenetic mapping of 18S ribosomal RNA (18S rRNA gene did not follow the chromosome diversification in the family. The dynamic evolution of the repeated units of rRNA genes generates patterns of chromosomal distribution that do not help follows the phylogenetic relationships among taxa. The presence of B chromosomes in cichlids is of particular interest because they may not be represented in

  13. Computer Assisted Mechanical Axis and Kinematic TKA

    Science.gov (United States)

    McEwen, Peter; Mahoharan, Varaguna

    2016-01-01

    Introduction: Total knee arthroplasty (TKA) has traditionally been and largely continues to be aligned mechanically, that being with a neutral coronal plane mechanical tibiofemoral axis and a joint line orientated at 900 to this axis. Femoral component rotation is set by gap balancing or by externally rotating 30 from any of a number femoral reference lines. This produces a rectangular flexion gap and relaxes patellar tracking. Kinematic alignment (KA) is an alternative technique that aims to restore premorbid alignment, joint orientation and ligament tension. The basic premise for this technique is based on evidence that the medial and lateral femoral condyles consistently equate to cylinders of equal or near equal size and that therefore with a fixed radius, cruciate retaining implant, matched distal femoral, posterior femoral and proximal tibial resections, accounting for bone and cartilage already lost will reproduce the premorbid joint line and restore native premorbid kinematics. Femoral rotation is therefore referenced off the prearthritic posterior condylar axis (PCA) that is on average internally rotated to the AP axis. Kinematic alignment therefore has the potential to challenge patellar tracking, increase patellar load and potentially increase patellar complications. Method: Case control study – level of evidence III-2. Between November 2012 and June 2013 the senior author completed 104 consecutive computer assisted (CAS) kinematically aligned total knee arthroplasties (TKA) with a cruciate retaining, fixed bearing, single radius implant. The results of these surgeries were compared with the results of 91 consecutive CAS mechanically aligned TKA done between November 2011 and October 2012 using the same navigation system and implant Implant sizing and positioning as well as gap measurement and ligament balance was done with computer assistance in all cases. Data was collected prospectively and analysed retrospectively. Results: The Oxford Knee Score

  14. Lift Augmentation for Vertical Axis Wind Turbines

    Directory of Open Access Journals (Sweden)

    Gerald M Angle II

    2010-12-01

    Full Text Available The concept of harnessing wind power has been around for centuries, and is first recorded by the Persians in 900 AD. These early uses of wind power were for the processing of food, particularly grinding grains, and consisted of stationary blades around a horizontal axis, the precursor to today’s horizontal axis wind turbines (HAWT. Technology for these wind mills was essentially the same until the 1930’s when advances in aircraft propeller theories were applied to the blades of the turbine. During this development period, which has since remained basically unchanged, the design push was for increasingly larger propellers requiring heavy and costly transmissions, generators, and support towers to be installed. An alternative concept to the HAWT was developed by Georges Darrieus [5], which utilized a vertical shaft and is known as a vertical axis wind turbine (VAWT. The scientific development of the concept did not gain strong attention until the 1970’s due to the perceived low efficiency of this style. This perception was due in part to the portion of the blade’s rotary path that is adverse to the generation of power. This efficiency loss can be minimized by the mechanical movement of the blade, relative to the airflow during the upwind portion of the blades’ rotational path. Since, circulation control can alter the forces generated by an airfoil, it could be used to increase the efficiency of a VAWT by increasing the torque produced on the downwind portion of the path, while removing the need for a physical change in angle of attack. With the recent upturn in petroleum costs and global warming concerns, interest in renewable energy technologies have been reinvigorated, in particular the desire for advanced wind energy technologies, including the application of lift augmentation techniques. One of these techniques is to utilize circulation control to enhance the lifting capacity of the blades based on the location of the blade in the

  15. ATP independent and ATP dependent chromatin remodeling in wheat

    International Nuclear Information System (INIS)

    Unraveling the biochemistry of chromatin dynamics during DNA replication, repair, recombination as well as transcription is the current challenge in biology. The nucleosomes containing histone octamer are the crucial elements responsible for winding and unwinding eukaryotic DNA. During DNA centric events, these nucleosomes translocate along the DNA with concomitant covalent modifications of histones. We explored these mechanisms in wheat seedlings after irradiation with survivable dose of 60Co-γ radiations. The histones isolated from irradiated seedlings showed that global acetylation of H3 decreased and H4 increased in dose depend manner till 100 grays. Time course of individual modifications showed that for H3K4 and H3K9 acetylation decreased, whereas H3S10, phosphorylation increased. There were fluctuations in acetylation of H4K5, H4K12 and H4K16, whereas H4K8 showed hyperacetylation. We found ATP-dependent chromatin remodeling activity as trans-transfer of the nucleosomes from wheat native donor chromatin on a labeled nucleosome positioning sequence and cis-transfer of the mononucleosomes in vitro. However, there was no significant change in this activity in extracts obtained from irradiated wheat seedlings. This is the first report on, demonstration of ATP-dependent chromatin remodeling activity and site specific H3 and H4 modifications in response to exposure to ionizing radiation in case of plants. (author)

  16. Remodeling of skin nerve fibers during burn wound healing

    Institute of Scientific and Technical Information of China (English)

    Yongqiang Feng; Xia Li; Rui Zhang; Yu Liu; Tingting Leng; Yibing Wang

    2010-01-01

    Burn wound healing involves a complex sequence of processes.Recent studies have revealed that skin reinnervation may have an impact on physiological wound repair.Few studies have addressed the process of reinnervation and morphological changes in regenerated nerve fibers.The regeneration of neurites during full-thickness burn wound healing was determined by immunofluorescent staining using an anti-neurofilament protein monoclonal antibody,and three-dimensional morphology was observed under a laser scanning confocal microscope.Morphology and the volume fraction of collagen and nerve fibers were measured.Skin reinnervation increased during wound healing,peaked during the proliferative scar stage,and then decreased to lower levels during the maturation period.The results from the skin nerve fibers correlated with those from collagen using semi-quantitative analysis.Disintegration and fragmentation were observed frequently in samples from the proliferative stage,and seldom occurred during the maturation stage.There was a remodeling process of regenerated nerve fibers during wound healing,which comprised changed innervation density and topical morphology.The mechanism of remodeling for nerve fibers requires further investigation.

  17. Remodeling in the ischemic heart: the stepwise progression for heart

    Directory of Open Access Journals (Sweden)

    J.G. Mill

    2011-09-01

    Full Text Available Abstract Coronary artery disease is the leading cause of death in the developed world and in developing countries. Acute mortality from acute myocardial infarction (MI has decreased in the last decades. However, the incidence of heart failure (HF in patients with healed infarcted areas is increasing. Therefore, HF prevention is a major challenge to the health system in order to reduce healthcare costs and to provide a better quality of life. Animal models of ischemia and infarction have been essential in providing precise information regarding cardiac remodeling. Several of these changes are maladaptive, and they progressively lead to ventricular dilatation and predispose to the development of arrhythmias, HF and death. These events depend on cell death due to necrosis and apoptosis and on activation of the inflammatory response soon after MI. Systemic and local neurohumoral activation has also been associated with maladaptive cardiac remodeling, predisposing to HF. In this review, we provide a timely description of the cardiovascular alterations that occur after MI at the cellular, neurohumoral and electrical level and discuss the repercussions of these alterations on electrical, mechanical and structural dysfunction of the heart. We also identify several areas where insufficient knowledge limits the adoption of better strategies to prevent HF development in chronically infarcted individuals.

  18. Cardiac remodeling and physical training post myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    Michael; A; Garza; Emily; A; Wason; John; Q; Zhang

    2015-01-01

    After myocardial infarction(MI), the heart undergoes extensive myocardial remodeling through the accumulation of fibrous tissue in both the infarcted and noninfarcted myocardium, which distorts tissue structure, increases tissue stiffness, and accounts for ventricular dysfunction. There is growing clinical consensus that exercise training may beneficially alter the course of post-MI myocardial remodeling and improve cardiac function. This review summarizes the present state of knowledge regarding the effect of post-MI exercise training on infarcted hearts. Due to the degree of difficulty to study a viable human heart at both protein and molecular levels, most of the detailed studies have been performed by using animal models. Although there are some negative reports indicating that post-MI exercise may further cause deterioration of the wounded hearts, a growing body of research from both human and animal experiments demonstrates that post-MI exercise may beneficially alter the course of wound healing and improve cardiac function. Furthermore, the improved function is likely due to exercise training-induced mitigation of reninangiotensin-aldosterone system, improved balance between matrix metalloproteinase-1 and tissue inhibitor of matrix metalloproteinase-1, favorable myosin heavy chain isoform switch, diminished oxidative stress, enhanced antioxidant capacity, improved mitochondrial calcium handling, and boosted myocardial angiogenesis. Additionally, meta-analyses revealed that exercise-based cardiac rehabilitation has proven to be effective, and remains one of the least expensive therapies for both the prevention and treatment of cardiovascular disease, and prevents re-infarction.

  19. Cell Wall Composition, Biosynthesis and Remodeling during Pollen Tube Growth

    Directory of Open Access Journals (Sweden)

    Jean-Claude Mollet

    2013-03-01

    Full Text Available The pollen tube is a fast tip-growing cell carrying the two sperm cells to the ovule allowing the double fertilization process and seed setting. To succeed in this process, the spatial and temporal controls of pollen tube growth within the female organ are critical. It requires a massive cell wall deposition to promote fast pollen tube elongation and a tight control of the cell wall remodeling to modify the mechanical properties. In addition, during its journey, the pollen tube interacts with the pistil, which plays key roles in pollen tube nutrition, guidance and in the rejection of the self-incompatible pollen. This review focuses on our current knowledge in the biochemistry and localization of the main cell wall polymers including pectin, hemicellulose, cellulose and callose from several pollen tube species. Moreover, based on transcriptomic data and functional genomic studies, the possible enzymes involved in the cell wall remodeling during pollen tube growth and their impact on the cell wall mechanics are also described. Finally, mutant analyses have permitted to gain insight in the function of several genes involved in the pollen tube cell wall biosynthesis and their roles in pollen tube growth are further discussed.

  20. Vascular Remodelling and Mesenchymal Transition in Systemic Sclerosis

    Directory of Open Access Journals (Sweden)

    Pier Andrea Nicolosi

    2016-01-01

    Full Text Available Fibrosis of the skin and of internal organs, autoimmunity, and vascular inflammation are hallmarks of Systemic Sclerosis (SSc. The injury and activation of endothelial cells, with hyperplasia of the intima and eventual obliteration of the vascular lumen, are early features of SSc. Reduced capillary blood flow coupled with deficient angiogenesis leads to chronic hypoxia and tissue ischemia, enforcing a positive feed-forward loop sustaining vascular remodelling, further exacerbated by extracellular matrix accumulation due to fibrosis. Despite numerous developments and a growing number of controlled clinical trials no treatment has been shown so far to alter SSc natural history, outlining the need of further investigation in the molecular pathways involved in the pathogenesis of the disease. We review some processes potentially involved in SSc vasculopathy, with attention to the possible effect of sustained vascular inflammation on the plasticity of vascular cells. Specifically we focus on mesenchymal transition, a key phenomenon in the cardiac and vascular development as well as in the remodelling of injured vessels. Recent work supports the role of transforming growth factor-beta, Wnt, and Notch signaling in these processes. Importantly, endothelial-mesenchymal transition may be reversible, possibly offering novel cues for treatment.

  1. Pay attention to cardiac remodeling in cancer cachexia.

    Science.gov (United States)

    Zheng, Yawen; Chen, Han; Li, Xiaoqing; Sun, Yuping

    2016-07-01

    Cancer cachexia is a complex and multifaceted disease state characterized by fatigue, weakness, and loss of skeletal muscle and adipose tissue. Recently, the profound negative effects of cancer cachexia on cardiac tissue draw much attention, which is likely to contribute to mortality in tumor-bearing animals. The mechanism of cardiac remodeling is not so clear and involved with a series of molecular alterations. In cancer cachexia model, progressive loss of left ventricular mass and decrease in myocardial function is observed and cardiac autonomic functions are altered. Levels of several emerging cardiovascular neurohormones are found elevating in patients with cancer, but it is still controversial whether the changes could reflect the heart injury accurately. The remedy for cardiac remodeling has been explored. It is showed that exercise can modulate signaling pathways activated by wasting cytokines and impact on the resulting outcomes on heart adaptation. Some drugs, such as bisoprolol, spironolactone, perindopril, tandospirone, and simvastatin, can mitigate adverse effects of the tumor on the heart and prolong survival. PMID:27108265

  2. Defective membrane remodeling in neuromuscular diseases: insights from animal models.

    Directory of Open Access Journals (Sweden)

    Belinda S Cowling

    Full Text Available Proteins involved in membrane remodeling play an essential role in a plethora of cell functions including endocytosis and intracellular transport. Defects in several of them lead to human diseases. Myotubularins, amphiphysins, and dynamins are all proteins implicated in membrane trafficking and/or remodeling. Mutations in myotubularin, amphiphysin 2 (BIN1, and dynamin 2 lead to different forms of centronuclear myopathy, while mutations in myotubularin-related proteins cause Charcot-Marie-Tooth neuropathies. In addition to centronuclear myopathy, dynamin 2 is also mutated in a dominant form of Charcot-Marie-Tooth neuropathy. While several proteins from these different families are implicated in similar diseases, mutations in close homologues or in the same protein in the case of dynamin 2 lead to diseases affecting different tissues. This suggests (1 a common molecular pathway underlying these different neuromuscular diseases, and (2 tissue-specific regulation of these proteins. This review discusses the pathophysiology of the related neuromuscular diseases on the basis of animal models developed for proteins of the myotubularin, amphiphysin, and dynamin families. A better understanding of the common mechanisms between these neuromuscular disorders will lead to more specific health care and therapeutic approaches.

  3. Remodeling of a nontreated displaced parasymphyseal fracture of a child.

    Science.gov (United States)

    Kerem, Hakan; Usluer, Ayşen; Yoleri, Levent

    2011-07-01

    There have been considerable advances in the management of craniomaxillofacial injuries in children. Conservative approaches such as close observation, a liquid-to-soft diet, and analgesics can be used for the management of mandibular fractures without displacement and malocclusion. However, displaced fractures need to be an anatomic reduction and immobilization. The basic principle of displaced mandibular fractures in both children and adults is the stabilization of fracture fragments forming the pretraumatic contour and occlusion state until osteosynthesis occurs. The major differences of pediatric fractures from adults are the flexibility of bones and very rapid healing pattern. Therefore, reduction in pediatric age group must be accomplished earlier. This case was an 11-year-old boy presented with a severely displaced parasymphyseal mandibular fracture resulting from a fall. He was given a soft diet and analgesic, given anti-inflammatory treatment of edema, and scheduled for operation. Subsequently, it was surprisingly observed that there was a significant improvement in the fracture line on the 12th posttraumatic day. The comparison of maxillofacial computed tomographic scans of the first and 12th posttraumatic days revealed a noteworthy remodeling and a remarkable approximation of the fracture lines. It can be concluded that bone remodelization in the pediatric age groups is perfect and very rapid, even in severely displaced fractures. PMID:21772181

  4. Retinal Remodeling: Concerns, Emerging Remedies, and Future Prospects

    Directory of Open Access Journals (Sweden)

    Vidhyasankar eKrishnamoorthy

    2016-02-01

    Full Text Available Deafferentation results not only in sensory loss, but also in a variety of alterations in the postsynaptic circuitry. These alterations may have detrimental impact on potential treatment strategies. Progressive loss of photoreceptors in retinal degenerative diseases, such as retinitis pigmentosa and age-related macular degeneration, leads to several changes in the remnant retinal circuitry. Müller glial cells undergo hypertrophy and form a glial seal. The second- and third-order retinal neurons undergo morphological, biochemical and physiological alterations. A result of these alterations is that retinal ganglion cells (RGCs, the output neurons of the retina, become hyperactive and exhibit spontaneous, oscillatory bursts of spikes. This aberrant electrical activity degrades the signal-to-noise ratio in RGC responses, and thus the quality of information they transmit to the brain. These changes in the remnant retina, collectively termed retinal remodeling, pose challenges for genetic, cellular and bionic approaches to restore vision. It is therefore crucial to understand the nature of retinal remodeling, how it affects the ability of remnant retina to respond to novel therapeutic strategies, and how to ameliorate its effects. In this article, we discuss these topics, and suggest that the pathological state of the retinal output following photoreceptor loss is reversible, and therefore, amenable to restorative strategies.

  5. Pulmonary arterial remodeling in chronic obstructive pulmonary disease is lobe dependent.

    Science.gov (United States)

    Wrobel, Jeremy P; McLean, Catriona A; Thompson, Bruce R; Stuart-Andrews, Christopher R; Paul, Eldho; Snell, Gregory I; Williams, Trevor J

    2013-09-01

    Abstract Pulmonary arterial remodeling has been demonstrated in patients with severe chronic obstructive pulmonary disease (COPD), but it is not known whether lobar heterogeneity of remodeling occurs. Furthermore, the relationship between pulmonary hypertension (PH) and pulmonary arterial remodeling in COPD has not been established. Muscular pulmonary arterial remodeling in arteries 0.10-0.25 mm in diameter was assessed in COPD-explanted lungs and autopsy controls. Remodeling was quantified as the percentage wall thickness to vessel diameter (%WT) using digital image analysis. Repeat measures mixed-effects remodeling for %WT was performed according to lobar origin (upper and lower), muscular pulmonary arterial size (small, medium, and large), and echocardiography-based pulmonary arterial pressure (no PH, mild PH, and moderate-to-severe PH). Lobar perfusion and emphysema indices were determined from ventilation-perfusion and computed tomography scans, respectively. Overall, %WT was greater in 42 subjects with COPD than in 5 control subjects ([Formula: see text]). Within the COPD group, %WT was greater in the upper lobes ([Formula: see text]) and in the small muscular pulmonary arteries ([Formula: see text]). Lobar differences were most pronounced in medium and large arteries. Lobar emphysema index was not associated with arterial remodeling. However, there was a significant positive relationship between the lobar perfusion index and pulmonary arterial remodeling ([Formula: see text]). The presence of PH on echocardiography showed only a trend to a small effect on lower lobe remodeling. The pattern of pulmonary arterial remodeling in COPD is complicated and lobe dependent. Differences in regional blood flow partially account for the lobar heterogeneity of pulmonary arterial remodeling in COPD. PMID:24618551

  6. Uncemented Total Hip Replacement Stem Loosening after Long Term Compressive Stress Application: A Simulated FEA Study of Cortical Bone Remodeling

    Science.gov (United States)

    Jung, Duk-Young; Tsutsumi, Sadami; Nakai, Ryusuke; Ikeuchi, Ken; Sekel, Ron

    The purpose of this study is to predict with the use of FEA, the differing predisposition to cortical bone resorption and subsequent distal migration of an un-cemented femoral hip replacement stem subjected to long term biomechanical high compressive stresses, while varying the load angles, the material properties of the stem, and the stem length. A two-dimensional hip model was constructed to estimate the minimum principle stresses (P3) and migration magnitudes. Bone remodeling at the interface between the bone and the prosthesis was performed by comparison of the local compressive stress to physiological stress values governing bone resorption. With respect to load angles, migrations of the hip prosthesis did not occur with load angles between 63° and 74° load angle in relation to the longitudinal axis of the bony femur, as the compressive stress generated on the cortical bone was under the criteria threshold for bone resorption (-50MPa). In addition, the magnitude of migration (17%decrease) was relatively more sensitive to changes in stem length than those (92%decrease) of changes of material properties. In conclusion, using an FEA model for bone remodeling, based on the high compressive stresses exerted on distal cortical bone, it is possible to estimate migration magnitudes of cementless hip prostheses in the long term. The load angles have been shown to be an important parameter affecting the migration magnitudes and furthermore, it can be demonstrated that the stiffer materials and reduction of stem length can decrease the migration of cementless hip prosthesis in the long term.

  7. Model for performance prediction in multi-axis machining

    CERN Document Server

    Lavernhe, Sylvain; Lartigue, Claire; 10.1007/s00170-007-1001-4

    2009-01-01

    This paper deals with a predictive model of kinematical performance in 5-axis milling within the context of High Speed Machining. Indeed, 5-axis high speed milling makes it possible to improve quality and productivity thanks to the degrees of freedom brought by the tool axis orientation. The tool axis orientation can be set efficiently in terms of productivity by considering kinematical constraints resulting from the set machine-tool/NC unit. Capacities of each axis as well as some NC unit functions can be expressed as limiting constraints. The proposed model relies on each axis displacement in the joint space of the machine-tool and predicts the most limiting axis for each trajectory segment. Thus, the calculation of the tool feedrate can be performed highlighting zones for which the programmed feedrate is not reached. This constitutes an indicator for trajectory optimization. The efficiency of the model is illustrated through examples. Finally, the model could be used for optimizing process planning.

  8. Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

    OpenAIRE

    Yerle Martine; Ducos Alain; Pinton Alain

    2003-01-01

    Abstract A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+) translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5) were elaborated and...

  9. Sex chromosome evolution: platypus gene mapping suggests that part of the human X chromosome was originally autosomal.

    OpenAIRE

    Watson, J M; Spencer, J. A.; Riggs, A D; Graves, J.A.

    1991-01-01

    To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in all mammals, revealing that this region was part of an ancient mammalian X chromosome. However, we now report that several genes located on the short arm of the human X chromosome...

  10. HIF-1α-PDK1 axis-induced active glycolysis plays an essential role in macrophage migratory capacity.

    Science.gov (United States)

    Semba, Hiroaki; Takeda, Norihiko; Isagawa, Takayuki; Sugiura, Yuki; Honda, Kurara; Wake, Masaki; Miyazawa, Hidenobu; Yamaguchi, Yoshifumi; Miura, Masayuki; Jenkins, Dana M R; Choi, Hyunsung; Kim, Jung-Whan; Asagiri, Masataka; Cowburn, Andrew S; Abe, Hajime; Soma, Katsura; Koyama, Katsuhiro; Katoh, Manami; Sayama, Keimon; Goda, Nobuhito; Johnson, Randall S; Manabe, Ichiro; Nagai, Ryozo; Komuro, Issei

    2016-01-01

    In severely hypoxic condition, HIF-1α-mediated induction of Pdk1 was found to regulate glucose oxidation by preventing the entry of pyruvate into the tricarboxylic cycle. Monocyte-derived macrophages, however, encounter a gradual decrease in oxygen availability during its migration process in inflammatory areas. Here we show that HIF-1α-PDK1-mediated metabolic changes occur in mild hypoxia, where mitochondrial cytochrome c oxidase activity is unimpaired, suggesting a mode of glycolytic reprogramming. In primary macrophages, PKM2, a glycolytic enzyme responsible for glycolytic ATP synthesis localizes in filopodia and lammelipodia, where ATP is rapidly consumed during actin remodelling processes. Remarkably, inhibition of glycolytic reprogramming with dichloroacetate significantly impairs macrophage migration in vitro and in vivo. Furthermore, inhibition of the macrophage HIF-1α-PDK1 axis suppresses systemic inflammation, suggesting a potential therapeutic approach for regulating inflammatory processes. Our findings thus demonstrate that adaptive responses in glucose metabolism contribute to macrophage migratory activity. PMID:27189088

  11. Nonrandom chromosomal changes in human malignant cells

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J D

    1977-01-01

    The role of chromosomal changes in human malignant cells has been the subject of much debate. The observation of nonrandom chromosomal changes has become well recognized in chronic myelogenous leukemia, and more recently in acute myelogenous leukemia. In the present report, data are presented on the sites of duplication of chromosome No. 1 in hematologic disorders. Trisomy for region lq25 to lq32 was observed in every one of 34 patients whose cells showed duplication of some part of chromosome No. 1. Adjacent regions lq21 to lq25, and lq32 to lqter, also were trisomic in the majority of patients. Two patients had deletions, one of lq32 to qter, and the other, of lp32 to pter. The sites of chromosomal breaks leading to trisomy differ from those involved in balanced reciprocal translocations. Some of these sites are sometimes, but not always, vulnerable in constitutional chromosomal abnormalities. The nature of the proliferative advantage conferred on myeloid cells by these chromosomal changes is unknown.

  12. Chromosome number evolution in skippers (Lepidoptera, Hesperiidae).

    Science.gov (United States)

    Lukhtanov, Vladimir A

    2014-01-01

    Lepidoptera (butterflies and moths), as many other groups of animals and plants, simultaneously represent preservation of ancestral karyotype in the majority of families with a high degree of chromosome number instability in numerous independently evolved phylogenetic lineages. However, the pattern and trends of karyotype evolution in some Lepidoptera families are poorly studied. Here I provide a survey of chromosome numbers in skippers (family Hesperiidae) based on intensive search and analysis of published data. I demonstrate that the majority of skippers preserve the haploid chromosome number n=31 that seems to be an ancestral number for the Hesperiidae and the order Lepidoptera at whole. However, in the tribe Baorini the derived number n=16 is the most typical state which can be used as a (syn)apomorphic character in further phylogenetic investigations. Several groups of skippers display extreme chromosome number variations on within-species (e.g. the representatives of the genus Carcharodus Hübner, [1819]) and between-species (e.g. the genus Agathymus Freeman, 1959) levels. Thus, these groups can be used as model systems for future analysis of the phenomenon of chromosome instability. Interspecific chromosomal differences are also shown to be useful for discovering and describing new cryptic species of Hesperiidae representing in such a way a powerful tool in biodiversity research. Generally, the skipper butterflies promise to be an exciting group that will significantly contribute to the growing knowledge of patterns and processes of chromosome evolution. PMID:25610542

  13. Chromosome number evolution in skippers (Lepidoptera, Hesperiidae

    Directory of Open Access Journals (Sweden)

    Vladimir Lukhtanov

    2014-11-01

    Full Text Available Lepidoptera (butterflies and moths, as many other groups of animals and plants, simultaneously represent preservation of ancestral karyotype in the majority of families with a high degree of chromosome number instability in numerous independently evolved phylogenetic lineages. However, the pattern and trends of karyotype evolution in some Lepidoptera families are poorly studied. Here I provide a survey of chromosome numbers in skippers (family Hesperiidae based on intensive search and analysis of published data. I demonstrate that the majority of skippers preserve the haploid chromosome number n=31 that seems to be an ancestral number for the Hesperiidae and the order Lepidoptera at whole. However, in the tribe Baorini the derived number n=16 is the most typical state which can be used as a (synapomorphic character in further phylogenetic investigations. Several groups of skippers display extreme chromosome number variations on within-species (e.g. the representatives of the genus Carcharodus Hübner, [1819] and between-species (e.g. the genus Agathymus Freeman, 1959 levels. Thus, these groups can be used as model systems for future analysis of the phenomenon of chromosome instability. Interspecific chromosomal differences are also shown to be useful for discovering and describing new cryptic species of Hesperiidae representing in such a way a powerful tool in biodiversity research. Generally, the skipper butterflies promise to be an exciting group that will significantly contribute to the growing knowledge of patterns and processes of chromosome evolution.

  14. Group 3 chromosome bin maps of wheat and their relationship to rice chromosome 1.

    Science.gov (United States)

    Munkvold, J D; Greene, R A; Bermudez-Kandianis, C E; La Rota, C M; Edwards, H; Sorrells, S F; Dake, T; Benscher, D; Kantety, R; Linkiewicz, A M; Dubcovsky, J; Akhunov, E D; Dvorák, J; Miftahudin; Gustafson, J P; Pathan, M S; Nguyen, H T; Matthews, D E; Chao, S; Lazo, G R; Hummel, D D; Anderson, O D; Anderson, J A; Gonzalez-Hernandez, J L; Peng, J H; Lapitan, N; Qi, L L; Echalier, B; Gill, B S; Hossain, K G; Kalavacharla, V; Kianian, S F; Sandhu, D; Erayman, M; Gill, K S; McGuire, P E; Qualset, C O; Sorrells, M E

    2004-10-01

    The focus of this study was to analyze the content, distribution, and comparative genome relationships of 996 chromosome bin-mapped expressed sequence tags (ESTs) accounting for 2266 restriction fragments (loci) on the homoeologous group 3 chromosomes of hexaploid wheat (Triticum aestivum L.). Of these loci, 634, 884, and 748 were mapped on chromosomes 3A, 3B, and 3D, respectively. The individual chromosome bin maps revealed bins with a high density of mapped ESTs in the distal region and bins of low density in the proximal region of the chromosome arms, with the exception of 3DS and 3DL. These distributions were more localized on the higher-resolution group 3 consensus map with intermediate regions of high-mapped-EST density on both chromosome arms. Gene ontology (GO) classification of mapped ESTs was not significantly different for homoeologous group 3 chromosomes compared to the other groups. A combined analysis of the individual bin maps using 537 of the mapped ESTs revealed rearrangements between the group 3 chromosomes. Approximately 232 (44%) of the consensus mapped ESTs matched sequences on rice chromosome 1 and revealed large- and small-scale differences in gene order. Of the group 3 mapped EST unigenes approximately 21 and 32% matched the Arabidopsis coding regions and proteins, respectively, but no chromosome-level gene order conservation was detected. PMID:15514041

  15. Five-axis rough machining for impellers

    Institute of Scientific and Technical Information of China (English)

    Ruolong QI; Weijun LIU; Hongyou BIAN; Lun LI

    2009-01-01

    The most important components used in aero-space, ships, and automobiles are designed with free form surfaces. An impeller is one of the most important components that is difficult to machine because of its twisted blades. Rough machining is recognized as the most crucial procedure influencing machining efficiency and is critical for the finishing process. An integrated rough machining course with detailed algorithms is presented in this paper. An algorithm for determining the minimum distance between two surfaces is applied to estimate the tool size. The space between two blades that will be cleared from the roughcast is divided to generate CC points. The tool axis vector is confirmed based on flank milling using a simple method that could eliminate global interference between the tool and the blades. The result proves that the machining methodology presented in this paper is useful and successful.

  16. Polarized triple-axis spectrometer TASP

    Energy Technology Data Exchange (ETDEWEB)

    Boeni, P.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    The polarized triple-axis spectrometer TASP at SINQ has been optimized for measuring magnetic cross sections in condensed matter. The neutrons are polarized or analyzed either by means of benders or Heusler monochromators. The beam divergence, i.e. the intensity, and the spectral range of the neutrons is rather large because of the supermirror coatings of the feeding neutron guide. The intensity can be further increased at the sample position by means of a focussing monochromator and a focussing anti-trumpet. The end position of TASP allows the tailoring of the neutron beam already before the monochromator and to scatter neutrons over very wide ranges of angles. (author) 6 figs., 1 tab., 8 refs.

  17. Remodeling of ribosomal genes in somatic cells by Xenopus egg extract

    DEFF Research Database (Denmark)

    Østrup, Olga; Hyttel, Poul; Klærke, Dan Arne;

    2011-01-01

    remodeling complex component SNF2H without affecting occupancy of the transcription factor UBF and the stress silencers SUV39H1 and SIRT1. During this process, nucleolar localization of UBF and SIRT1 is not altered. On contrary, azacytidine pre-treatment has an adverse effect on rDNA remodeling induced by...

  18. A Novel Algorithm to Quantify Coronary Remodeling Using Inferred Normal Dimensions

    Directory of Open Access Journals (Sweden)

    Breno A. A. Falcão

    2015-01-01

    Full Text Available Background:Vascular remodeling, the dynamic dimensional change in face of stress, can assume different directions as well as magnitudes in atherosclerotic disease. Classical measurements rely on reference to segments at a distance, risking inappropriate comparison between dislike vessel portions.Objective:to explore a new method for quantifying vessel remodeling, based on the comparison between a given target segment and its inferred normal dimensions.Methods:Geometric parameters and plaque composition were determined in 67 patients using three-vessel intravascular ultrasound with virtual histology (IVUS-VH. Coronary vessel remodeling at cross-section (n = 27.639 and lesion (n = 618 levels was assessed using classical metrics and a novel analytic algorithm based on the fractional vessel remodeling index (FVRI, which quantifies the total change in arterial wall dimensions related to the estimated normal dimension of the vessel. A prediction model was built to estimate the normal dimension of the vessel for calculation of FVRI.Results:According to the new algorithm, “Ectatic” remodeling pattern was least common, “Complete compensatory” remodeling was present in approximately half of the instances, and “Negative” and “Incomplete compensatory” remodeling types were detected in the remaining. Compared to a traditional diagnostic scheme, FVRI-based classification seemed to better discriminate plaque composition by IVUS-VH.Conclusion:Quantitative assessment of coronary remodeling using target segment dimensions offers a promising approach to evaluate the vessel response to plaque growth/regression.

  19. A mechanism for arteriolar remodeling based on maintenance of smooth muscle cell activation

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; Mulvany, Michael John; Holstein-Rathlou, N.-H.

    2008-01-01

    Structural adaptation in arterioles is part of normal vascular physiology but is also seen in disease states such as hypertension. Smooth muscle cell (SMC) activation has been shown to be central to microvascular remodeling. We hypothesize that, in a remodeling process driven by SMC activation...

  20. Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping.

    Science.gov (United States)

    Trask, B; van den Engh, G; Mayall, B; Gray, J W

    1989-11-01

    Maternal and paternal homologues of many chromosome types can be differentiated on the basis of their peak position in Hoechst 33258 versus chromomycin A3 bivariate flow karyotypes. We demonstrate here the magnitude of DNA content differences among normal chromosomes of the same type. Significant peak-position differences between homologues were observed for an average of four chromosome types in each of the karyotypes of 98 different individuals. The frequency of individuals with differences in homologue peak positions varied among chromosome types: e.g., chromosome 15, 61%; chromosome 3, 4%. Flow karyotypes of 33 unrelated individuals were compared to determine the range of peak position among normal chromosomes. Chromosomes Y, 21, 22, 15, 16, 13, 14, and 19 were most heteromorphic, and chromosomes 2-8 and X were least heteromorphic. The largest chromosome 21 was 45% larger than the smallest 21 chromosome observed. The base composition of the variable regions differed among chromosome types. DNA contents of chromosome variants determined from flow karyotypes were closely correlated to measurements of DNA content made of gallocyanin chrome alum-stained metaphase chromosomes on slides. Fluorescence in situ hybridization with chromosome-specific repetitive sequences indicated that variability in their copy number is partly responsible for peak-position variability in some chromosomes. Heteromorphic chromosomes are identified for which parental flow karyotype information will be essential if de novo rearrangements resulting in small DNA content changes are to be detected with flow karyotyping. PMID:2479266

  1. Adaptation through chromosomal inversions in Anopheles

    Directory of Open Access Journals (Sweden)

    Diego eAyala

    2014-05-01

    Full Text Available Chromosomal inversions have been repeatedly involved in local adaptation in a large number of animals and plants. The ecological and behavioral plasticity of Anopheles species - human malaria vectors - is mirrored by high amounts of polymorphic inversions. The adaptive significance of chromosomal inversions has been consistently attested by strong and significant correlations between their frequencies and a number of phenotypic traits. Here, we provide an extensive literature review of the different adaptive traits associated with chromosomal inversions in the genus Anopheles. Traits having important consequences for the success of present and future vector control measures, such as insecticide resistance and behavioral changes, are discussed.

  2. Chromosomal abnormalities in patients with sperm disorders

    Directory of Open Access Journals (Sweden)

    L. Y. Pylyp

    2013-02-01

    Full Text Available Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intracytoplasmic sperm injection in particular, enable the transmission of chromosomal abnormalities to the progeny. Therefore, cytogenetic studies are important in patients with male factor infertility before assisted reproduction treatment. The purpose of the current study was to investigate the types and frequencies of chromosomal abnormalities in 724 patients with infertility and to estimate the risk of chromosomal abnormalities detection in subgroups of patients depending on the severity of spermatogenic disruption, aiming at identifying groups of patients in need of cytogenetic studies. Karyotype analysis was performed in 724 blood samples of men attending infertility clinic. Chromosomal preparation was performed by standard techniques. At least 20 GTG-banded metaphase plates with the resolution from 450 to 750 bands per haploid set were analysed in each case. When chromosomal mosaicism was suspected, this number was increased to 50. Abnormal karyotypes were observed in 48 (6.6% patients, including 67% of autosomal abnormalities and 33% of gonosomal abnormalities. Autosomal abnormalities were represented by structural rearrangements. Reciprocal translocations were the most common type of structural chromosomal abnormalities in the studied group, detected with the frequency of 2.6% (n = 19, followed by Robertsonian translocation, observed with the frequency of 1.2% (n = 9. The frequency of inversions was 0.6% (n = 4. Gonosomal abnormalities included 14 cases

  3. Can experimental data in humans verify the finite element-based bone remodeling algorithm?

    DEFF Research Database (Denmark)

    Wong, C.; Gehrchen, P.M.; Kiaer, T.

    2008-01-01

    spine operated on with pedicle screws between L4 and L5. The stress shielding effect was also examined. The bone remodeling results were compared with prospective bone mineral content measurements of 4 patients. They were measured after surgery, 3-, 6- and 12-months postoperatively. RESULTS: After 1......STUDY DESIGN: A finite element analysis-based bone remodeling study in human was conducted in the lumbar spine operated on with pedicle screws. Bone remodeling results were compared to prospective experimental bone mineral content data of patients operated on with pedicle screws. OBJECTIVE: The......, in the human spine, the bone remodeling algorithms have neither been evaluated experimentally nor been examined by comparing to unsystematic experimental data. METHODS: The site-specific and nonsite-specific iterative bone remodeling algorithms were applied to a finite element model of the lumbar...

  4. Persistent severe hypereosinophilic asthma is not associated with airway remodeling.

    Science.gov (United States)

    Alagha, Khuder; Jarjour, Baihas; Bommart, Sebastien; Aviles, Berta; Varrin, Muriel; Gamez, Anne Sophie; Molinari, Nicolas; Vachier, Isabelle; Paganin, Fabrice; Chanez, Pascal; Bourdin, Arnaud

    2015-02-01

    Hypereosinophilic asthma (HEA) is considered as a specific severe asthma phenotype. Whether eosinophils have a link with airway remodeling characterized by pathological (thickening of the basement membrane), functional (persistent airflow impairment and decline in lung function) and imaging features (increase airway wall thickness at CT scan) is still debated. In a one year prospective cohort of 142 severe asthma patients (according to IMI), 14 persistent HEA patients (defined by a persistent blood eosinophilia >500/mm(3) at two consecutive visits) were identified and compared with ten patients without any blood eosinophilia during the follow-up period (NEA, blood eosinophilia always Bronchial biopsies obtained at enrollment were stained for eosinophils (EG2) and basement membrane thickness (BM) was quantified. Imaging by CT scan acquisition was standardized and bronchial abnormalities quantified. ACQ score and exacerbations were prospectively recorded. HEA was not associated with preeminent features of airway remodeling assessed by airflow impairment (Best ever FEV1 values 97% ± 20 in HEA vs. 80 ± 24% in NEA, p = 0.020), decline of FEV1 (FEV1 Decline 40 ± 235 ml/y in HEA vs. 19 ± 40 ml/y in NEA, P = 0.319), submucosal abnormalities (BM thickness 7.80 ± 2.66 μm in HEA vs. 6.84 ± 2.59 in NEA, p = 0.37) and airway wall thickening at CT-scan (0.250 ± 0.036 mm vs. 0.261 ± 0.043, p = 0.92). Eosinophils blood count was inversely correlated with semiquantitative imaging score (rho -0.373, p = 0.039). Smoking history and positive skin prick tests were independent risk factors for increased BM thickening. Outcomes were similar in both populations (Control and exacerbations). Persistent HEA is not associated with evidences of airway remodeling. PMID:25592243

  5. Left ventricular structure and remodeling in patients with COPD

    Directory of Open Access Journals (Sweden)

    Pelà G

    2016-05-01

    Full Text Available Giovanna Pelà,1 Mauro Li Calzi,1 Silvana Pinelli,1 Roberta Andreoli,1 Nicola Sverzellati,2 Giuseppina Bertorelli,1 Matteo Goldoni,1 Alfredo Chetta11Department of Clinical and Experimental Medicine, 2Department of Surgery, University Medical School, University Hospital Parma, Parma, ItalyBackground: Data on cardiac alterations such as left ventricular (LV hypertrophy, diastolic dysfunction, and lower stroke volume in patients with COPD are discordant. In this study, we investigated whether early structural and functional cardiac changes occur in patients with COPD devoid of manifest cardiovascular disease, and we assessed their associations with clinical and functional features.Methods: Forty-nine patients with COPD belonging to all Global Initiative for Chronic Obstructive Lung Disease (GOLD classes were enrolled and compared with 36 controls. All subjects underwent clinical history assessment, lung function testing, blood pressure measurement, electrocardiography, and conventional and Doppler tissue echocardiography. Patients were also subjected to computed tomography to quantify emphysema score.Results: Patients with COPD had lower LV cavity associated with a marked increase in relative wall thickness (RWT, suggesting concentric remodeling without significant changes in LV mass. RWT was significantly associated with ratio of the forced expiratory volume in 1 second to the forced vital capacity and emphysema score and was the only cardiac parameter that – after multivariate analysis – significantly correlated with COPD conditions in all individuals. Receiver operating characteristic curve analysis showed that RWT (with a cutoff point of 0.42 predicted the severity of COPD with 83% specificity and 56% sensitivity (area under the curve =0.69, 95% confidence interval =0.59–0.81. Patients with COPD showed right ventricular to be functional but no structural changes.Conclusion: Patients with COPD without evident cardiovascular disease

  6. Relationship of cardiac arrhythmias to myocar- dial remodeling and expression of adhesion molecules in patients with mitral valve prolapse

    Directory of Open Access Journals (Sweden)

    A.V. Yagoda

    Conclusion. Myocardial remodeling and dysregulation of cell adhesion proteins are recorded in young patients with MVP and arrhythmias. Relaionship of severity of arrhythmic syndrome to myocardial remodeling and VCAM-1 level was revealed.

  7. Chromosome landmarks and autosome-sex chromosome translocations in Rumex hastatulus, a plant with XX/XY1Y2 sex chromosome system.

    Science.gov (United States)

    Grabowska-Joachimiak, Aleksandra; Kula, Adam; Książczyk, Tomasz; Chojnicka, Joanna; Sliwinska, Elwira; Joachimiak, Andrzej J

    2015-06-01

    Rumex hastatulus is the North American endemic dioecious plant with heteromorphic sex chromosomes. It is differentiated into two chromosomal races: Texas (T) race characterised by a simple XX/XY sex chromosome system and North Carolina (NC) race with a polymorphic XX/XY1Y2 sex chromosome system. The gross karyotype morphology in NC race resembles the derived type, but chromosomal changes that occurred during its evolution are poorly understood. Our C-banding/DAPI and fluorescence in situ hybridization (FISH) experiments demonstrated that Y chromosomes of both races are enriched in DAPI-positive sequences and that the emergence of polymorphic sex chromosome system was accompanied by the break of ancestral Y chromosome and switch in the localization of 5S rDNA, from autosomes to sex chromosomes (X and Y2). Two contrasting domains were detected within North Carolina Y chromosomes: the older, highly heterochromatinised, inherited from the original Y chromosome and the younger, euchromatic, representing translocated autosomal material. The flow-cytometric DNA estimation showed ∼3.5 % genome downsizing in the North Carolina race. Our results are in contradiction to earlier reports on the lack of heterochromatin within Y chromosomes of this species and enable unambiguous identification of autosomes involved in the autosome-heterosome translocation, providing useful chromosome landmarks for further studies on the karyotype and sex chromosome differentiation in this species. PMID:25394583

  8. Extracellular Matrix Remodeling by Dynamic Strain in a Three-Dimensional Tissue-Engineered Human Airway Wall Model

    OpenAIRE

    Choe, Melanie M.; Sporn, Peter H. S.; Swartz, Melody A.

    2006-01-01

    Airway wall remodeling is a hallmark of asthma, characterized by subepithelial thickening and extracellular matrix (ECM) remodeling. Mechanical stress due to hyperresponsive smooth muscle cells may contribute to this remodeling, but its relevance in a three-dimensional environment (where the ECM plays an important role in modulating stresses felt by cells) is unclear. To characterize the effects of dynamic compression in ECM remodeling in a physiologically relevant three-dimensional environme...

  9. Visualization of yeast chromosomal DNA

    Science.gov (United States)

    Lubega, Seth

    1990-01-01

    The DNA molecule is the most significant life molecule since it codes the blue print for other structural and functional molecules of all living organisms. Agarose gel electrophoresis is now being widely used to separate DNA of virus, bacteria, and lower eukaryotes. The task was undertaken of reviewing the existing methods of DNA fractionation and microscopic visualization of individual chromosonal DNA molecules by gel electrophoresis as a basis for a proposed study to investigate the feasibility of separating DNA molecules in free fluids as an alternative to gel electrophoresis. Various techniques were studied. On the molecular level, agarose gel electrophoresis is being widely used to separate chromosomal DNA according to molecular weight. Carl and Olson separate and characterized the entire karyotype of a lab strain of Saccharomyces cerevisiae. Smith et al. and Schwartz and Koval independently reported the visualization of individual DNA molecules migrating through agarose gel matrix during electrophoresis. The techniques used by these researchers are being reviewed in the lab as a basis for the proposed studies.

  10. Dynamic changes in paternal X-chromosome activity during imprinted X-chromosome inactivation in mice

    OpenAIRE

    Patrat, Catherine; Okamoto, Ikuhiro; Diabangouaya, Patricia; Vialon, Vivian; Le Baccon, Patricia; Chow, Jennifer; Heard, Edith

    2009-01-01

    In mammals, X-chromosome dosage compensation is achieved by inactivating one of the two X chromosomes in females. In mice, X inactivation is initially imprinted, with inactivation of the paternal X (Xp) chromosome occurring during preimplantation development. One theory is that the Xp is preinactivated in female embryos, because of its previous silence during meiosis in the male germ line. The extent to which the Xp is active after fertilization and the exact time of onset of X-linked gene si...

  11. Tracking Chromosome Evolution in Southern African Gerbils Using Flow-Sorted Chromosome Paints

    OpenAIRE

    Knight, L.I.; Ng, B. L.; Cheng, W; Fu, B.; Yang, F.; Rambau, R V

    2013-01-01

    Desmodillus and Gerbilliscus (formerly Tatera) comprise a monophyletic group of gerbils (subfamily Gerbillinae) which last shared an ancestor approximately 8 million years ago; diploid chromosome number variation among the species ranges from 2n = 36 to 2n = 50. In an attempt to shed more light on chromosome evolution and speciation in these rodents, we compared the karyotypes of 7 species, representing 3 genera, based on homology data revealed by chromosome painting with probes derived from ...

  12. Sex Chromosome Evolution in Amniotes: Applications for Bacterial Artificial Chromosome Libraries

    OpenAIRE

    Janes, Daniel E.; Nicole Valenzuela; Tariq Ezaz; Chris Amemiya; Edwards, Scott V.

    2011-01-01

    Variability among sex chromosome pairs in amniotes denotes a dynamic history. Since amniotes diverged from a common ancestor, their sex chromosome pairs and, more broadly, sex-determining mechanisms have changed reversibly and frequently. These changes have been studied and characterized through the use of many tools and experimental approaches but perhaps most effectively through applications for bacterial artificial chromosome (BAC) libraries. Individual BAC clones carry 100–200 kb of seque...

  13. Remodelling of choroidal blood flow in radiation choroidopathy

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Hideo; Muraoka, Kanemitsu; Takahashi, Kyoichi; Sutoh, Noriko [Gunma Univ., Maebashi (Japan). School of Medicine

    1997-02-01

    Two males, aged 68 and 34 years each, presented with radiation retinopathy. One had received radiation therapy to the whole brain for intracranial metastasis of lung carcinoma 29 months before. The other underwent surgery and radiation for melanoma of the upper eyelid 15 years before. When examined by indocyanine green angiography. both cases showed vasoocclusive changes in the choroid involving the choriocapillaris and major vessels in the affected fundus area. In one eye with severe retinal vascular lesions in the superior temporal quadrant, the vortex vein in the quadrant had obliterated. The venous blood in this quadrant was drained into the inferior temporal vortex vein crossing the presumed watershed zone temporal to the macula. Collaterals had formed between choroidal arteries and between choroidal veins. These cases illustrate that choroidal vascular lesions may be present in radiation retinopathy, that the former may be more pronounced than the latter and that choroidal vessels may undergo extensive remodelling to compensate for the disturbed choroidal circulation. (author)

  14. Stress-induced remodeling of hippocampal CA3 pyramidal neurons.

    Science.gov (United States)

    McEwen, Bruce S

    2016-08-15

    The discovery of steroid hormone receptors in brain regions that mediate virtually every aspect of brain function has broadened the definition of 'neuroendocrinology' to include the reciprocal communication between the brain and the body via hormonal and neural pathways. The brain is the central organ of stress and adaptation to stress because it perceives and determines what is threatening, as well as determining the behavioral and physiological responses to the stressor. The adult and developing brain possess remarkable structural and functional plasticity in response to stress, including neurogenesis leading to neuronal replacement, dendritic remodeling, and synapse turnover. Stress causes an imbalance of neural circuitry subserving cognition, decision-making, anxiety and mood that can alter expression of those behaviors and behavioral states. The two Brain Research papers noted in this review played an important role in triggering these advances. This article is part of a Special Issue entitled SI:50th Anniversary Issue. PMID:26740399

  15. Extracellular matrix bioscaffolds in tissue remodeling and morphogenesis.

    Science.gov (United States)

    Swinehart, Ilea T; Badylak, Stephen F

    2016-03-01

    During normal morphogenesis the extracellular matrix (ECM) influences cell motility, proliferation, apoptosis, and differentiation. Tissue engineers have attempted to harness the cell signaling potential of ECM to promote the functional reconstruction, if not regeneration, of injured or missing adult tissues that otherwise heal by the formation of scar tissue. ECM bioscaffolds, derived from decellularized tissues, have been used to promote the formation of site appropriate, functional tissues in many clinical applications including skeletal muscle, fibrocartilage, lower urinary tract, and esophageal reconstruction, among others. These scaffolds function by the release or exposure of growth factors and cryptic peptides, modulation of the immune response, and recruitment of progenitor cells. Herein, we describe this process of ECM induced constructive remodeling and examine similarities to normal tissue morphogenesis. PMID:26699796

  16. Alternative lengthening of telomeres: remodeling the telomere architecture

    Directory of Open Access Journals (Sweden)

    Dimitri eConomos

    2013-02-01

    Full Text Available To escape from the normal limits on proliferative potential, cancer cells must employ a means to counteract the gradual telomere attrition that accompanies semi-conservative DNA replication. While the majority of human cancers do this by up-regulating telomerase enzyme activity, most of the remainder use a homologous recombination-mediated mechanism of telomere elongation known as alternative lengthening of telomeres (ALT. Many molecular details of the ALT pathway are unknown, and even less is known regarding the mechanisms by which this pathway is activated. Here, we review current findings about telomere structure in ALT cells, including DNA sequence, shelterin content, and heterochromatic state. We speculate that remodeling of the telomere architecture may contribute to the emergence and maintenance of the ALT phenotype.

  17. Sliding and peeling of histone during chromatin remodelling

    CERN Document Server

    Garai, Ashok; Chowdhury, Debashish

    2011-01-01

    ATP-dependent chromatin remodeling enzymes (CRE) are bio-molecular motors in eukaryotic cells. These are driven by a chemical fuel, namely, adenosine triphosphate (ATP). CREs actively participate in many cellular processes that require accessibility of specific stretches of DNA which are packaged as chromatin. The basic unit of chromatin is a nucleosome where 146 bp $\\sim$ 50 nm of a double stranded DNA (dsDNA) is wrapped around a spool formed by histone proteins. We investigate the mechanism of peeling of the histone spool, and its complete detachment, from the dsDNA by a CRE. Our two-state model of a CRE captures effectively two distinct chemical (or conformational) states in the mechano-chemical cycle of each ATP-dependent CRE. We calculate the mean times for histone detachment. Our predictions on the ATP-dependence of the measurable quantities can be tested by carrying out {\\it in-vitro} experiments.

  18. Meshless methods in biomechanics bone tissue remodelling analysis

    CERN Document Server

    Belinha, Jorge

    2014-01-01

    This book presents the complete formulation of a new advanced discretization meshless technique: the Natural Neighbour Radial Point Interpolation Method (NNRPIM). In addition, two of the most popular meshless methods, the EFGM and the RPIM, are fully presented. Being a truly meshless method, the major advantages of the NNRPIM over the FEM, and other meshless methods, are the remeshing flexibility and the higher accuracy of the obtained variable field. Using the natural neighbour concept, the NNRPIM permits to determine organically the influence-domain, resembling the cellulae natural behaviour. This innovation permits the analysis of convex boundaries and extremely irregular meshes, which is an advantage in the biomechanical analysis, with no extra computational effort associated.   This volume shows how to extend the NNRPIM to the bone tissue remodelling analysis, expecting to contribute with new numerical tools and strategies in order to permit a more efficient numerical biomechanical analysis.

  19. Protein receptor-independent plasma membrane remodeling by HAMLET

    DEFF Research Database (Denmark)

    Nadeem, Aftab; Sanborn, Jeremy; Gettel, Douglas L.;

    2015-01-01

    A central tenet of signal transduction in eukaryotic cells is that extra-cellular ligands activate specific cell surface receptors, which orchestrate downstream responses. This "protein-centric" view is increasingly challenged by evidence for the involvement of specialized membrane domains in...... signal transduction. Here, we propose that membrane perturbation may serve as an alternative mechanism to activate a conserved cell-death program in cancer cells. This view emerges from the extraordinary manner in which HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) kills a wide range of...... tumor cells in vitro and demonstrates therapeutic efficacy and selectivity in cancer models and clinical studies. We identify a "receptor independent" transformation of vesicular motifs in model membranes, which is paralleled by gross remodeling of tumor cell membranes. Furthermore, we find that HAMLET...

  20. The relationship between gap junctional remodeling and human atrial fibrillation

    Institute of Scientific and Technical Information of China (English)

    李大强; 冯义柏; 张会琴

    2004-01-01

    @@ Atrial fibrillation (AF) is currently the most common cardiac tachyarrhythmia in clinical practice. AF has a tendency to become more persistent over time. Progression of an underlying disease is one explanation. Another possible explanation is electrical, structural, and gap junctional remodeling of the atrium by repetitive induction of AF.1 The expression level and distribution of it have close relation with the conduction velocity of electrical activation in the atrium. The aim of the present study was to investigate the alternations of the expression and distribution of (connexin 40, Cx 40) and (connexin 43, Cx 43) in the right atrial appendages of the patients with AF by laser confocal scanning microscopy and Western blot technique.

  1. H3837 DARHT's first dual-axis shot

    International Nuclear Information System (INIS)

    Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic HydroTest (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. With high-strength steel walls over half an inch thick, the boom box confined the shot completely without taxing the penetrating capability of the DARHT x-ray beams; in addition, over three inches of tungsten attenuation in the beamlines prevented saturation of the camera systems. The boombox was staged within the DACS (Dual Axis Confinement system) with a source-to-object distance of 1.33 m for each Axis; radiographic magnifications were 4 and 4.5 for Axes I and II respectively. The first Axis provided a pulse of 60 ns width and dose 450 R at 1 m, while the second Axis provided four pulses of the following widths and doses: 20 ns, 85 R; 45 ns, 169 R; 65 ns, 233 R; 65 ns, 225 R; beam spot sizes were measured (50% MTF LANL definition) as < 1.7 mm (Axis I) and 1.9-2.8 mm (Axis II), with less than 1.5 mm beam motion between Axis II pulses. The Bucky Grid camera system was used for Axis I, while Axis II had a unique four-frame camera developed jointly by MIT Lincoln Laboratory. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II. Shock speed in the material and other time-dependent properties such as material damage progression are measured using the time-evolved data from Axis II, while density reconstructions are made from the views of Axes I and II. The radiographs from Axis I and Axis II pulse 3 are compared in order to generate a three-dimensional image of the shocked material, enabling

  2. Haploidization via Chromosome Elimination: Means and Mechanisms.

    Science.gov (United States)

    Ishii, Takayoshi; Karimi-Ashtiyani, Raheleh; Houben, Andreas

    2016-04-29

    The ability to generate haploids and subsequently induce chromosome doubling significantly accelerates the crop breeding process. Haploids have been induced through the generation of plants from haploid tissues (in situ gynogenesis and androgenesis) and through the selective loss of a parental chromosome set via inter- or intraspecific hybridization. Here, we focus on the mechanisms responsible for this selective chromosome elimination. CENH3, a variant of the centromere-specific histone H3, has been exploited to create an efficient method of haploid induction, and we discuss this approach in some detail. Parallels have been drawn with chromosome-specific elimination, which occurs as a normal part of differentiation and sex determination in many plant and animal systems. PMID:26772657

  3. Cancer chromosomal instability: therapeutic and diagnostic challenges

    OpenAIRE

    McGranahan, Nicholas; Burrell, Rebecca A.; Endesfelder, David; Novelli, Marco R; Swanton, Charles

    2012-01-01

    This review provides a much-needed translational perspective into the issue of aneuploidy and chromosomal instability, discussing the prognostic value of CIN assessment in human tumours, methods to analyze it and how it could be therapeutically targeted.

  4. Lattice animal model of chromosome organization

    Science.gov (United States)

    Iyer, Balaji V. S.; Arya, Gaurav

    2012-07-01

    Polymer models tied together by constraints of looping and confinement have been used to explain many of the observed organizational characteristics of interphase chromosomes. Here we introduce a simple lattice animal representation of interphase chromosomes that combines the features of looping and confinement constraints into a single framework. We show through Monte Carlo simulations that this model qualitatively captures both the leveling off in the spatial distance between genomic markers observed in fluorescent in situ hybridization experiments and the inverse decay in the looping probability as a function of genomic separation observed in chromosome conformation capture experiments. The model also suggests that the collapsed state of chromosomes and their segregation into territories with distinct looping activities might be a natural consequence of confinement.

  5. Chromosome studies in the genus Jatropha L.

    Directory of Open Access Journals (Sweden)

    R.Sasikala and M.Paramathma

    2010-07-01

    Full Text Available The inflorescences of ten species of the genus Jatropha were fixed in Cornoy’s fluid (6:3:1. Acetocarmine stain (2% wasused for staining the pollen mother cells. Seven species exhibited 11 bivalents and 2n =22 and x=11. But the two otherspecies, J.villosa var. villosa and J.villosa var. ramnadensis showed only 10 bivalents and 2n number of 20 chromosomesand x=10. The study concluded the occurrence of two kinds of haploid chromosome numbers of n =10 and n =11. ExceptJatropha tanjorensis, cytological investigation in all species exhibited normal and complete pairing and bivalent formationin metaphase I and equal separation of chromosome in anaphase and indicated that the course of meiosis was normal.Jatropha tanjorensis did not exhibit normal course of meiosis and no proper count of chromosomes could be made. Presentchromosomal studies in Jatropha revealed the existence of two basic chromosomes numbers x = 5 and x = 6.

  6. System for the analysis of plant chromosomes

    International Nuclear Information System (INIS)

    The paper describes a computer system for the automation workers of recognition analysis and interpretation of plant chromosomes. This system permit to carry out the analysis in a more comfortable and faster way, using the image processing techniques

  7. Left ventricular structure and remodeling in patients with COPD

    Science.gov (United States)

    Pelà, Giovanna; Li Calzi, Mauro; Pinelli, Silvana; Andreoli, Roberta; Sverzellati, Nicola; Bertorelli, Giuseppina; Goldoni, Matteo; Chetta, Alfredo

    2016-01-01

    Background Data on cardiac alterations such as left ventricular (LV) hypertrophy, diastolic dysfunction, and lower stroke volume in patients with COPD are discordant. In this study, we investigated whether early structural and functional cardiac changes occur in patients with COPD devoid of manifest cardiovascular disease, and we assessed their associations with clinical and functional features. Methods Forty-nine patients with COPD belonging to all Global Initiative for Chronic Obstructive Lung Disease (GOLD) classes were enrolled and compared with 36 controls. All subjects underwent clinical history assessment, lung function testing, blood pressure measurement, electrocardiography, and conventional and Doppler tissue echocardiography. Patients were also subjected to computed tomography to quantify emphysema score. Results Patients with COPD had lower LV cavity associated with a marked increase in relative wall thickness (RWT), suggesting concentric remodeling without significant changes in LV mass. RWT was significantly associated with ratio of the forced expiratory volume in 1 second to the forced vital capacity and emphysema score and was the only cardiac parameter that – after multivariate analysis – significantly correlated with COPD conditions in all individuals. Receiver operating characteristic curve analysis showed that RWT (with a cutoff point of 0.42) predicted the severity of COPD with 83% specificity and 56% sensitivity (area under the curve =0.69, 95% confidence interval =0.59–0.81). Patients with COPD showed right ventricular to be functional but no structural changes. Conclusion Patients with COPD without evident cardiovascular disease exhibit significant changes in LV geometry, resulting in concentric remodeling. In all individuals, RWT was significantly and independently related to COPD. However, its prognostic role should be determined in future studies. PMID:27257378

  8. Muscle metabolic remodelling in response to endurance exercise in salmonids

    Directory of Open Access Journals (Sweden)

    Andrea J Morash

    2014-11-01

    Full Text Available Phenotypic plasticity of skeletal muscle is relevant to swimming performance and metabolism in fishes, especially those that undergo extreme locomotory feats, such as seasonal migration. However, the influence of endurance exercise and the molecular mechanisms coordinating this remodelling are not well understood. The present study examines muscle metabolic remodelling associated with endurance exercise in fed rainbow trout as compared to migrating salmon. Trout were swum for 4 weeks at 1.5BL/s, a speed similar to that of migrating salmon and red and white muscles were sampled after each week. We quantified changes in key enzymes in aerobic and carbohydrate metabolism (citrate synthase (CS, β-hydroxyacyl-CoA dehydrogenase (HOAD, hexokinase (HK and changes in mRNA expression of major regulators of metabolic phenotype (AMPK, PPARs and lipid (carnitine palmitoyltransferase, CPT I, protein (aspartate aminotransferase, AST and carbohydrate (HK oxidation pathways. After one week of swimming substantial increases were seen in AMPK and PPARα mRNA expression and of their downstream target genes, CPTI and HK in red muscle. However, significant changes in CS and HK activity occurred only after 4 weeks. In contrast, there were few changes in mRNA expression and enzyme activities in white muscle over the 4-weeks. Red muscle results mimic those found in migrating salmon suggesting a strong influence of exercise on red muscle phenotype. In white muscle, only changes in AMPK and PPAR expression were similar to that seen with migrating salmon. However, in contrast to exercise alone, in natural migration HK decreased while AST increased suggesting that white muscle plays a role in supplying fuel and intermediates possibly through tissue breakdown during prolonged fasting. Dissecting individual and potentially synergistic effects of multiple stressors will enable us to determine major drivers of the metabolic phenotype and their impacts on whole animal

  9. The effect of radiation dose on mouse skeletal muscle remodeling

    International Nuclear Information System (INIS)

    The purpose of this study was to determine the effect of two clinically relevant radiation doses on the susceptibility of mouse skeletal muscle to remodeling. Alterations in muscle morphology and regulatory signaling were examined in tibialis anterior and gastrocnemius muscles after radiation doses that differed in total biological effective dose (BED). Female C57BL/6 (8-wk) mice were randomly assigned to non-irradiated control, four fractionated doses of 4 Gy (4x4 Gy; BED 37 Gy), or a single 16 Gy dose (16 Gy; BED 100 Gy). Mice were sacrificed 2 weeks after the initial radiation exposure. The 16 Gy, but not 4x4 Gy, decreased total muscle protein and RNA content. Related to muscle regeneration, both 16 Gy and 4x4 Gy increased the incidence of central nuclei containing myofibers, but only 16 Gy increased the extracellular matrix volume. However, only 4x4 Gy increased muscle 4-hydroxynonenal expression. While both 16 Gy and 4x4 Gy decreased IIB myofiber mean cross-sectional area (CSA), only 16 Gy decreased IIA myofiber CSA. 16 Gy increased the incidence of small diameter IIA and IIB myofibers, while 4x4 Gy only increased the incidence of small diameter IIB myofibers. Both treatments decreased the frequency and CSA of low succinate dehydrogenase activity (SDH) fibers. Only 16 Gy increased the incidence of small diameter myofibers having high SDH activity. Neither treatment altered muscle signaling related to protein turnover or oxidative metabolism. Collectively, these results demonstrate that radiation dose differentially affects muscle remodeling, and these effects appear to be related to fiber type and oxidative metabolism

  10. Specificity analysis of lectins and antibodies using remodeled glycoproteins.

    Science.gov (United States)

    Iskratsch, Thomas; Braun, Andreas; Paschinger, Katharina; Wilson, Iain B H

    2009-03-15

    Due to their ability to bind specifically to certain carbohydrate sequences, lectins are a frequently used tool in cytology, histology, and glycan analysis but also offer new options for drug targeting and drug delivery systems. For these and other potential applications, it is necessary to be certain as to the carbohydrate structures interacting with the lectin. Therefore, we used glycoproteins remodeled with glycosyltransferases and glycosidases for testing specificities of lectins from Aleuria aurantia (AAL), Erythrina cristagalli (ECL), Griffonia simplicifolia (GSL I-B(4)), Helix pomatia agglutinin (HPA), Lens culinaris (LCA), Lotus tetragonolobus (LTA), peanut (Arachis hypogaeae) (PNA), Ricinus communis (RCA I), Sambucus nigra (SNA), Vicia villosa (VVA), and wheat germ (Triticum vulgaris) (WGA) as well as reactivities of anti-carbohydrate antibodies (anti-bee venom, anti-horseradish peroxidase [anti-HRP], and anti-Lewis(x)). After enzymatic remodeling, the resulting neoglycoforms display defined carbohydrate sequences and can be used, when spotted on nitrocellulose or in enzyme-linked lectinosorbent assays, to identify the sugar moieties bound by the lectins. Transferrin with its two biantennary complex N-glycans was used as scaffold for gaining diverse N-glycosidic structures, whereas fetuin was modified using glycosidases to test the specificities of lectins toward both N- and O-glycans. In addition, alpha(1)-acid glycoprotein and Schistosoma mansoni egg extract were chosen as controls for lectin interactions with fucosylated glycans (Lewis(x) and core alpha1,3-fucose). Our data complement and expand the existing knowledge about the binding specificity of a range of commercially available lectins. PMID:19123999

  11. Estrogen enhances vasoconstrictive remodeling after injury in male rabbits

    Directory of Open Access Journals (Sweden)

    Francisco Y.A.

    2005-01-01

    Full Text Available The complete spectrum of estrogen vascular effects remains unclear. In particular, estrogen effects in the vascular response to profound injury in males have not been explored in detail. Therefore, we submitted 44 male New Zealand rabbits weighing 3.4 ± 0.6 kg to overdistention balloon injury of the right iliac artery. Rabbits were given 17ß-estradiol (5.45 µmol/day, sc or vehicle for 7 days before and 14 days after injury, when the arteries were examined by post-mortem histomorphometry. Arteriographic caliber was assessed in vivo at baseline and before sacrifice. On day 14 after injury, in vivo arteriographic caliber (baseline = 2.44 ± 0.43 mm was decreased by 23.1 ± 0.1% in controls and by 44.5 ± 0.1% in estrogen-treated rabbits (P < 0.001. Neither the neointimal area nor the neointima/media area ratio changed after estrogen treatment. Collagen fraction was increased in the media and neointima of estrogen-treated rabbits vs control (1.38 ± 1.30 vs 0.35 ± 0.67, respectively, P = 0.01. Taken together, these findings suggest that estrogen increased negative vascular remodeling. Transcription of endothelial and inducible nitric oxide synthases (eNOS and iNOS was analyzed by RT-PCR. eNOS mRNA expression was marginally increased after estrogen (P = 0.07 and injury. iNOS mRNA was increased 2- to 3-fold on day 14 after injury. With estrogen treatment, iNOS mRNA increased in uninjured arteries and exhibited a further 5.5-fold increase after injury. We concluded that estrogen increased lumen loss after balloon injury in male rabbits, likely by increased negative remodeling, which may be related to increased iNOS transcriptional rates.

  12. Thymoquinone inhibits inflammation, neoangiogenesis and vascular remodeling in asthma mice.

    Science.gov (United States)

    Su, Xinming; Ren, Yuan; Yu, Na; Kong, Lingfei; Kang, Jian

    2016-09-01

    Asthma is a chronic obstructive disease which is characterized by recurring airway inflammation, reversible airway obstruction, airway hyper responsiveness and vascular remodeling. Thymoquinone (TQ), an active ingredient isolated from Nigella sativa, was reported to exhibit anti-inflammation and anti-proliferation of in various cancer cells as well as epithelial cells. The aim of this study was to evaluate the effect of TQ on the inflammation, neoangiogenesis and vascular remodeling induced by Ovalbumin (OVA) in asthma mice in vivo and the anti-angiogenesis effects of TQ in VEGF-induced human umbilical vein endothelial cells (HUVECs) in vitro. Our results revealed that TQ inhibited the production of inflammatory factors interleukin-4/-5 (IL-4/-5) by enzyme-linked immunesorbent assay (ELISA). Immunohistochemistry analysis showed that the increase of platelet endothelial cell adhesion molecule-1, which is also known as CD31 and α-smooth muscle actinalpha (α-SMA) expression in asthma mice challenged by OVA was suppressed by TQ. Moreover, TQ suppressed the activation of VEGFR2-PI3K-Akt pathway and up-regulated the expression of Slit glycoprotein-2 (Slit-2) both in vivo and in vitro with the inhibition of tube information in HUVEC cells. Meanwhile immunofluorescence analysis showed that Slit-2 and Roundabout-4 (Robo-4) were co-expressing after TQ treatment in OVA-challenged asthma mice. Our study demonstrates that TQ attenuated the inflammatory reaction by antagonizing IL-4/-5 while the anti-neoangiogenesis effect of TQ is mediated by inhibition of vascular endothelial growth factor (VEGF) expression through VEGFR2/PI3K/Akt signaling pathway, which supports a potential role for TQ in ameliorating asthma. PMID:27240137

  13. Early remodeling of rat cardiac muscle induced by swimming training

    Directory of Open Access Journals (Sweden)

    Verzola R.M.M.

    2006-01-01

    Full Text Available The aim of the present investigation was to study the effect of acute swimming training with an anaerobic component on matrix metallopeptidase (MMP activity and myosin heavy chain gene expression in the rat myocardium. Animals (male Wistar rats, weighing approximately 180 g were trained for 6 h/day in 3 sessions of 2 h each for 1 to 5 consecutive days (N = 5 rats per group. Rats swam in basins 47 cm in diameter and 60 cm deep filled with water at 33 to 35ºC. After the training period a significant increase (P < 0.05 was observed in the heart weight normalized to body weight by about 22 and 35% in the groups that trained for 96 and 120 h, respectively. Blood lactate levels were significantly increased (P < 0.05 in all groups after all training sessions, confirming an anaerobic component. However, lactate levels decreased (P < 0.05 with days of training, suggesting that the animals became adapted to this protocol. Myosin heavy chain-ß gene expression, analyzed by real time PCR and normalized with GAPDH gene expression, showed a significant two-fold increase (P < 0.01 after 5 days of training. Zymography analysis of myocardium extracts indicated a single ~60-kDa activity band that was significantly increased (P < 0.05 after 72, 96, and 120 h, indicating an increased expression of MMP-2 and suggesting precocious remodeling. Furthermore, the presence of MMP-2 was confirmed by Western blot analysis, but not the presence of MMP-1 and MMP-3. Taken together, our results indicate that in these training conditions, the rat heart undergoes early biochemical and functional changes required for the adaptation to the new physiological condition by tissue remodeling.

  14. BMP-2 Is Involved in Scleral Remodeling in Myopia Development.

    Directory of Open Access Journals (Sweden)

    Honghui Li

    Full Text Available The development of myopia is associated with scleral remodeling, but it is unclear which factors regulate this process. This study investigated bone morphogenetic protein-2 (BMP-2 expression in the sclera of guinea pigs with lens-induced myopia (LIM and after recovery from myopia and evaluated the effect of BMP-2 on extracellular matrix (ECM synthesis in human scleral fibroblasts (HSFs cultured in vitro. Lens-induced myopia was brought about in two groups of guinea pigs (the lens-induced myopia and myopia recovery groups by placing -4.00 D lenses on the right eye for three weeks. The left eye served as a contralateral control. In the recovery group, the lenses were removed after one week. The refractive power and axial length of the eyes were measured, and the BMP-2 expression levels in the sclera were measured. After three weeks, the lens-induced eyes acquired relative myopia in both groups of guinea pigs. Immunostaining of the eyeballs revealed significantly decreased BMP-2 expression in the posterior sclera of the myopic eyes compared to the contralateral eyes. One week after lens removal, BMP-2 expression recovered, and no differences were observed between the experimental and contralateral eyes in the recovery group. HSFs were cultured with BMP-2 or transforming growth factor-β1 (TGF-β1. Type I and type III collagen synthesis was significantly up-regulated following BMP-2 treatment in culture after one and two weeks, but the ratio of type III to type I collagen mRNA was not increased. Biosynthesis of glycosaminoglycan (GAG and aggrecan was increased in HSFs treated with BMP-2. Some chondrogenesis-associated genes expression increased in HSFs treated with BMP-2. From this study, we concluded that BMP-2 is involved in scleral remodeling in the development and recovery of lens-induced myopia.

  15. BMP-2 Is Involved in Scleral Remodeling in Myopia Development

    Science.gov (United States)

    Li, Honghui; Cui, Dongmei; Zhao, Feng; Huo, Lijun; Hu, Jianmin; Zeng, Junwen

    2015-01-01

    The development of myopia is associated with scleral remodeling, but it is unclear which factors regulate this process. This study investigated bone morphogenetic protein-2 (BMP-2) expression in the sclera of guinea pigs with lens-induced myopia (LIM) and after recovery from myopia and evaluated the effect of BMP-2 on extracellular matrix (ECM) synthesis in human scleral fibroblasts (HSFs) cultured in vitro. Lens-induced myopia was brought about in two groups of guinea pigs (the lens-induced myopia and myopia recovery groups) by placing -4.00 D lenses on the right eye for three weeks. The left eye served as a contralateral control. In the recovery group, the lenses were removed after one week. The refractive power and axial length of the eyes were measured, and the BMP-2 expression levels in the sclera were measured. After three weeks, the lens-induced eyes acquired relative myopia in both groups of guinea pigs. Immunostaining of the eyeballs revealed significantly decreased BMP-2 expression in the posterior sclera of the myopic eyes compared to the contralateral eyes. One week after lens removal, BMP-2 expression recovered, and no differences were observed between the experimental and contralateral eyes in the recovery group. HSFs were cultured with BMP-2 or transforming growth factor-β1 (TGF-β1). Type I and type III collagen synthesis was significantly up-regulated following BMP-2 treatment in culture after one and two weeks, but the ratio of type III to type I collagen mRNA was not increased. Biosynthesis of glycosaminoglycan (GAG) and aggrecan was increased in HSFs treated with BMP-2. Some chondrogenesis-associated genes expression increased in HSFs treated with BMP-2. From this study, we concluded that BMP-2 is involved in scleral remodeling in the development and recovery of lens-induced myopia. PMID:25965995

  16. Biophysical stimulation of bone fracture repair, regeneration and remodelling

    Directory of Open Access Journals (Sweden)

    Chao E. Y.S.

    2003-12-01

    Full Text Available Biophysical stimulation to enhance bone fracture repair and bone regenerate maturation to restore its structural strength must rely on both the biological and biomechanical principle according to the local tissue environment and the type of mechanical stress to be born by the skeletal joint system. This paper reviews the possible interactions between biophysical stimuli and cellular responses in healing bone fractures and proceeds to speculate the prospects and limitations of different experimental models in evaluating and optimising such non-invasive interventions. It is important to realize that bone fracture repair has several pathways with various combinations of bone formation mechanisms, but there may only be one bone remodeling principle regulated by the hypothesis proposed by Wolff. There are different mechanical and biophysical stimuli that could provide effective augmentation of fracture healing and bone regenerate maturation. The key requirements of establishing these positive interactions are to define the precise cellular response to the stimulation signal in an in vitro environment and to use well-established animal models to quantify and optimise the therapeutic regimen in a time-dependent manner. This can only be achieved through research collaboration among different disciplines using scientific methodologies. In addition, the specific forms of biophysical stimulation and its dose effect and application timing must be carefully determined and validated. Technological advances in achieving focalized stimulus delivery with adjustable signal type and intensity, in the ability to monitor healing callus mechanical property non-invasively, and in the establishment of a robust knowledgebase to develop effective and reliable treatment protocols are the essential pre-requisites to make biophysical stimulation acceptable in the main arena of health care. Finally, it is important to bear in mind that successful fracture repair or bone

  17. VASCULAR REMODELING AND HEART RATE VARIABILITY IN DIFFERENT ANTIHYPERTENSIVE THERAPIES

    Directory of Open Access Journals (Sweden)

    E. D. Golovanova

    2008-01-01

    Full Text Available Aim. To study the effect of the long-term antihypertensive monotherapy with indapamide (Arifon Retard, 1,5 mg/d, metoprolol tartrate (Egilok Retard, 50 mg/d and combined therapy with indapamide and perindopril (Noliprel Forte, 1 tab/d: perindopril 4 mg and indapamide 1,25 mg on pulse wave velocity (PWV, cardio-ankle vascular index (CAVI and the sympathetic system activity.Material and methods. 88 patients, aged 30-59 y.o. (32 normotensive patients, 56 with arterial hypertension [HT] of 1-2 grades were examined. Biological age (BA was determined by the linear regression and the vascular wall age (VWA was estimated with the use of volume sphygmography (“VaSera-1000”, “Fucuda Denshi”, Japan. 39 patients with HT were randomized into 3 parallel groups with studied therapies lasted for 6 months. PWV, CAVI of the vessels of elastic, muscular and mixed types, blood pressure, measured in upper and lower extremities and heart rate variability (HRV were determined before and at the end of the therapies.Results. BA and VWA were elevated in all of patients with HT as compared with normotensive patients. The reduction in PWV and CAVI of the vessels of elastic and mixed types, HRV increase were found in patients with Arifon Retard monotherapy. Monotherapy with metoprolol significantly improved HVR without any influence on the vascular remodeling. Noliprel Forte significantly decreased in blood pressure in the upper and lower extremities, PWV and CAVI of the vessels of all types, decreased in VWA and increased in parasympathetic drive.Conclusion. Long-term therapy with Arifon Retard and Noliprel Forte resulted in decrease in vascular remodeling and increase in HRV simultaneously with significant antihypertensive effect in patients with HT. Metoprolol low doses therapy resulted in normalization of autonomic drive independently on antihypertensive action.

  18. Tie1 controls angiopoietin function in vascular remodeling and inflammation.

    Science.gov (United States)

    Korhonen, Emilia A; Lampinen, Anita; Giri, Hemant; Anisimov, Andrey; Kim, Minah; Allen, Breanna; Fang, Shentong; D'Amico, Gabriela; Sipilä, Tuomas J; Lohela, Marja; Strandin, Tomas; Vaheri, Antti; Ylä-Herttuala, Seppo; Koh, Gou Young; McDonald, Donald M; Alitalo, Kari; Saharinen, Pipsa

    2016-09-01

    The angiopoietin/Tie (ANG/Tie) receptor system controls developmental and tumor angiogenesis, inflammatory vascular remodeling, and vessel leakage. ANG1 is a Tie2 agonist that promotes vascular stabilization in inflammation and sepsis, whereas ANG2 is a context-dependent Tie2 agonist or antagonist. A limited understanding of ANG signaling mechanisms and the orphan receptor Tie1 has hindered development of ANG/Tie-targeted therapeutics. Here, we determined that both ANG1 and ANG2 binding to Tie2 increases Tie1-Tie2 interactions in a β1 integrin-dependent manner and that Tie1 regulates ANG-induced Tie2 trafficking in endothelial cells. Endothelial Tie1 was essential for the agonist activity of ANG1 and autocrine ANG2. Deletion of endothelial Tie1 in mice reduced Tie2 phosphorylation and downstream Akt activation, increased FOXO1 nuclear localization and transcriptional activation, and prevented ANG1- and ANG2-induced capillary-to-venous remodeling. However, in acute endotoxemia, the Tie1 ectodomain that is responsible for interaction with Tie2 was rapidly cleaved, ANG1 agonist activity was decreased, and autocrine ANG2 agonist activity was lost, which led to suppression of Tie2 signaling. Tie1 cleavage also occurred in patients with hantavirus infection. These results support a model in which Tie1 directly interacts with Tie2 to promote ANG-induced vascular responses under noninflammatory conditions, whereas in inflammation, Tie1 cleavage contributes to loss of ANG2 agonist activity and vascular stability. PMID:27548530

  19. Erythrocyte stiffness during morphological remodeling induced by carbon ion radiation.

    Directory of Open Access Journals (Sweden)

    Baoping Zhang

    Full Text Available The adverse effect induced by carbon ion radiation (CIR is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy or X-rays (2, 4, 6, and 12 Gy for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy. The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study

  20. Nicotine induces dendritic spine remodeling in cultured hippocampal neurons.

    Science.gov (United States)

    Oda, Akira; Yamagata, Kanato; Nakagomi, Saya; Uejima, Hiroshi; Wiriyasermkul, Pattama; Ohgaki, Ryuichi; Nagamori, Shushi; Kanai, Yoshikatsu; Tanaka, Hidekazu

    2014-01-01

    Cholinergic neurons in the CNS are involved in synaptic plasticity and cognition. Both muscarinic and nicotinic acetylcholine receptors (nAChRs) influence plasticity and cognitive function. The mechanism underlying nAChR-induced plasticity, however, has remained elusive. Here, we demonstrate morphological changes in dendritic spines following activation of α4β2* nAChRs, which are expressed on glutamatergic pre-synaptic termini of cultured hippocampal neurons. Exposure of the neurons to nicotine resulted in a lateral enlargement of spine heads. This was abolished by dihydro-β-erythroidine, an antagonist of α4β2* nAChRs, but not by α-bungarotoxin, an antagonist of α7 nAChRs. Tetanus toxin or a mixture of 2-amino-5-phosphonovaleric acid and 6-cyano-7-nitroquinoxaline-2,3-dione, antagonists of NMDA- and AMPA-type glutamate receptors, blocked the nicotine-induced spine remodeling. In addition, nicotine exerted full spine-enlarging response in the post-synaptic neuron whose β2 nAChR expression was knocked down. Finally, pre-treatment with nicotine enhanced the Ca(2+)-response of the neurons to glutamate. These data suggest that nicotine influences the activity of glutamatergic neurotransmission through the activation of pre-synaptic α4β2 nAChRs, resulting in the modulation of spinal architecture and responsiveness. The present findings may represent one of the cellular mechanisms underlying cholinergic tuning of brain function. Activation of nicotinic acetylcholine receptors (nAChRs) in brain influences plasticity and cognition. Here, activation of α4β2* nAChRs, which are expressed on glutamatergic presynaptic termini, results in the enlargement of dendritic spines through the modulation of the glutamatergic neurotransmission. The remodeled spinal architecture might be responsible for the change in responsiveness of neural circuitry, leading to cholinergic tuning of brain function. PMID:24117996

  1. Label Free Chromosome Translocation Detection with Silicon nanowires

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Andersen, Karsten Brandt; Frøhling, Kasper Bayer;

    HROMOSOME translocation, which is a rearrangement of arms between two chromosomes, is a major group of chromosome abnormalities leading to cancer. As a result, two derivative chromosomes with sequences coming from both chromosomes are formed. The current translocation detection method is a Fluore...

  2. Methods and compositions for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    2003-07-22

    Methods and compositions for chromosome-specific staining are provided. Compositions comprise heterogenous mixtures of labeled nucleic acid fragments having substantially complementary base sequences to unique sequence regions of the chromosomal DNA for which their associated staining reagent is specific. Methods include methods for making the chromosome-specific staining compositions of the invention, and methods for applying the staining compositions to chromosomes.

  3. The hierarchically organized splitting of chromosomal bands for all human chromosomes

    Directory of Open Access Journals (Sweden)

    Liehr Thomas

    2009-01-01

    Full Text Available Abstract Background Chromosome banding is widely used in cytogenetics. However, the biological nature of hierarchically organized splitting of chromosomal bands of human chromosomes is an enigma and has not been, as yet, studied. Results Here we present for the first time the hierarchically organized splitting of chromosomal bands in their sub-bands for all human chromosomes. To do this, array-proved multicolor banding (aMCB probe-sets for all human chromosomes were applied to normal metaphase spreads of three different G-band levels. We confirmed for all chromosomes to be a general principle that only Giemsa-dark bands split into dark and light sub-bands, as we demonstrated previously by chromosome stretching. Thus, the biological band splitting is in > 50% of the sub-bands different than implemented by the ISCN nomenclature suggesting also a splitting of G-light bands. Locus-specific probes exemplary confirmed the results of MCB. Conclusion Overall, the present study enables a better understanding of chromosome architecture. The observed difference of biological and ISCN band-splitting may be an explanation why mapping data from human genome project do not always fit the cytogenetic mapping.

  4. Y chromosome evolution: emerging insights into processes of Y chromosome degeneration

    Science.gov (United States)

    Bachtrog, Doris

    2014-01-01

    The human Y chromosome is intriguing not only because it harbours the master-switch gene determining gender but also because of its unusual evolutionary trajectory. Previously an autosome, Y chromosome evolution has been characterized by massive gene decay. Recent whole-genome and transcriptome analyses of Y chromosomes in humans and other primates, in Drosophila species as well as in plants have shed light on the current gene content of the Y, its origins and its long-term fate. Comparative analysis of young and old Y chromosomes have given further insights into the evolutionary and molecular forces triggering Y degeneration and its evolutionary destiny. PMID:23329112

  5. Localization of topoisomerase II in mitotic chromosomes

    OpenAIRE

    1985-01-01

    In the preceding article we described a polyclonal antibody that recognizes cSc-1, a major polypeptide component of the chicken mitotic chromosome scaffold. This polypeptide was shown to be chicken topoisomerase II. In the experiments described in the present article we use indirect immunofluorescence and immunoelectron microscopy to examine the distribution of topoisomerase II within intact chromosomes. We also describe a simple experimental protocol that differentiates antigens that are int...

  6. Female meiotic sex chromosome inactivation in chicken.

    Directory of Open Access Journals (Sweden)

    Sam Schoenmakers

    2009-05-01

    Full Text Available During meiotic prophase in male mammals, the heterologous X and Y chromosomes remain largely unsynapsed, and meiotic sex chromosome inactivation (MSCI leads to formation of the transcriptionally silenced XY body. In birds, the heterogametic sex is female, carrying Z and W chromosomes (ZW, whereas males have the homogametic ZZ constitution. During chicken oogenesis, the heterologous ZW pair reaches a state of complete heterologous synapsis, and this might enable maintenance of transcription of Z- and W chromosomal genes during meiotic prophase. Herein, we show that the ZW pair is transiently silenced, from early pachytene to early diplotene using immunocytochemistry and gene expression analyses. We propose that ZW inactivation is most likely achieved via spreading of heterochromatin from the W on the Z chromosome. Also, persistent meiotic DNA double-strand breaks (DSBs may contribute to silencing of Z. Surprisingly, gammaH2AX, a marker of DSBs, and also the earliest histone modification that is associated with XY body formation in mammalian and marsupial spermatocytes, does not cover the ZW during the synapsed stage. However, when the ZW pair starts to desynapse, a second wave of gammaH2AX accumulates on the unsynapsed regions of Z, which also show a reappearance of the DSB repair protein RAD51. This indicates that repair of meiotic DSBs on the heterologous part of Z is postponed until late pachytene/diplotene, possibly to avoid recombination with regions on the heterologously synapsed W chromosome. Two days after entering diplotene, the Z looses gammaH2AX and shows reactivation. This is the first report of meiotic sex chromosome inactivation in a species with female heterogamety, providing evidence that this mechanism is not specific to spermatogenesis. It also indicates the presence of an evolutionary force that drives meiotic sex chromosome inactivation independent of the final achievement of synapsis.

  7. Y chromosome microdeletions in Turkish infertile men

    OpenAIRE

    Zamani Ayse; Kutlu Ruhusen; Durakbasi-Dursun H; Gorkemli Huseyin; Acar Aynur

    2006-01-01

    AIMS: To detect the frequency and types of both chromosomal abnormalities and Y chromosome microdeletions in infertile men attending to our university intracytoplasmic sperm injection ICSI/IVF centre and fertile control subjects in our patient population. SETTINGS AND DESIGN: A total of 50 infertile men who were referred to IVF center of Meram medical faculty were selected for the molecular azospermia factor (AZF) screening program. MATERIALS AND METHODS: Karyotype analysis and polymeras...

  8. Demasculinization of the Anopheles gambiae X chromosome

    Directory of Open Access Journals (Sweden)

    Magnusson Kalle

    2012-05-01

    Full Text Available Abstract Background In a number of organisms sex-biased genes are non-randomly distributed between autosomes and the shared sex chromosome X (or Z. Studies on Anopheles gambiae have produced conflicting results regarding the underrepresentation of male-biased genes on the X chromosome and it is unclear to what extent sexual antagonism, dosage compensation or X-inactivation in the male germline, the evolutionary forces that have been suggested to affect the chromosomal distribution of sex-biased genes, are operational in Anopheles. Results We performed a meta-analysis of sex-biased gene expression in Anopheles gambiae which provides evidence for a general underrepresentation of male-biased genes on the X-chromosome that increased in significance with the observed degree of sex-bias. A phylogenomic comparison between Drosophila melanogaster, Aedes aegypti and Culex quinquefasciatus also indicates that the Anopheles X chromosome strongly disfavours the evolutionary conservation of male-biased expression and that novel male-biased genes are more likely to arise on autosomes. Finally, we demonstrate experimentally that transgenes situated on the Anopheles gambiae X chromosome are transcriptionally silenced in the male germline. Conclusion The data presented here support the hypothesis that the observed demasculinization of the Anopheles X chromosome is driven by X-chromosome inactivation in the male germline and by sexual antagonism. The demasculinization appears to be the consequence of a loss of male-biased expression, rather than a failure in the establishment or the extinction of male-biased genes.

  9. Delayed chromosomal instability induced by DNA damage.

    OpenAIRE

    Marder, B A; Morgan, W. F.

    1993-01-01

    DNA damage induced by ionizing radiation can result in gene mutation, gene amplification, chromosome rearrangements, cellular transformation, and cell death. Although many of these changes may be induced directly by the radiation, there is accumulating evidence for delayed genomic instability following X-ray exposure. We have investigated this phenomenon by studying delayed chromosomal instability in a hamster-human hybrid cell line by means of fluorescence in situ hybridization. We examined ...

  10. Plasmid and chromosome segregation in prokaryotes

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Bugge Jensen, Rasmus; Gerdes, Kenn

    2000-01-01

    Recent major advances in the understanding of prokaryotic DNA segregation have been achieved by using fluorescence microscopy to visualize the localization of cellular components. Plasmids and bacterial chromosomes are partitioned in a highly dynamic fashion, suggesting the presence of a mitotic......-like apparatus in prokaryotes. The identification of chromosomal homologues of the well-characterized plasmid partitioning genes indicates that there could be a general mechanism of bacterial DNA partitioning. Udgivelsesdato: July 1...

  11. Principles of chromosomal organization: lessons from yeast

    OpenAIRE

    Zimmer, Christophe; Fabre, Emmanuelle

    2011-01-01

    The spatial organization of genes and chromosomes plays an important role in the regulation of several DNA processes. However, the principles and forces underlying this nonrandom organization are mostly unknown. Despite its small dimension, and thanks to new imaging and biochemical techniques, studies of the budding yeast nucleus have led to significant insights into chromosome arrangement and dynamics. The dynamic organization of the yeast genome during interphase argues for both the physica...

  12. Bacterial Artificial Chromosome Mutagenesis Using Recombineering

    OpenAIRE

    Kumaran Narayanan; Qingwen Chen

    2011-01-01

    Gene expression from bacterial artificial chromosome (BAC) clones has been demonstrated to facilitate physiologically relevant levels compared to viral and nonviral cDNA vectors. BACs are large enough to transfer intact genes in their native chromosomal setting together with flanking regulatory elements to provide all the signals for correct spatiotemporal gene expression. Until recently, the use of BACs for functional studies has been limited because their large size has inherently presented...

  13. Assembly of Lampbrush Chromosomes from Sperm Chromatin

    OpenAIRE

    Gall, Joseph G.; Murphy, Christine

    1998-01-01

    We have examined the behavior of demembranated sperm heads when injected into the germinal vesicle (GV) of amphibian oocytes. Xenopus sperm heads injected into Xenopus GVs swelled immediately and within hours began to stain with an antibody against RNA polymerase II (Pol II). Over time each sperm head became a loose mass of chromosome-like threads, which by 24–48 h resolved into individually recognizable lampbrush chromosomes (LBCs). Although LBCs derived from sperm are unreplicated single ch...

  14. Sequence conservation on the Y chromosome

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, L.H.; Yang-Feng, L. [Yale Univ. School of Medicine, New Haven, CT (United States); Lau, C. [Univ. of California, San Francisco, CA (United States)

    1994-09-01

    The Y chromosome is present in all mammals and is considered to be essential to sex determination. Despite intense genomic research, only a few genes have been identified and mapped to this chromosome in humans. Several of them, such as SRY and ZFY, have been demonstrated to be conserved and Y-located in other mammals. In order to address the issue of sequence conservation on the Y chromosome, we performed fluorescence in situ hybridization (FISH) with DNA from a human Y cosmid library as a probe to study the Y chromosomes from other mammalian species. Total DNA from 3,000-4,500 cosmid pools were labeled with biotinylated-dUTP and hybridized to metaphase chromosomes. For human and primate preparations, human cot1 DNA was included in the hybridization mixture to suppress the hybridization from repeat sequences. FISH signals were detected on the Y chromosomes of human, gorilla, orangutan and baboon (Old World monkey) and were absent on those of squirrel monkey (New World monkey), Indian munjac, wood lemming, Chinese hamster, rat and mouse. Since sequence analysis suggested that specific genes, e.g. SRY and ZFY, are conserved between these two groups, the lack of detectable hybridization in the latter group implies either that conservation of the human Y sequences is limited to the Y chromosomes of the great apes and Old World monkeys, or that the size of the syntenic segment is too small to be detected under the resolution of FISH, or that homologeous sequences have undergone considerable divergence. Further studies with reduced hybridization stringency are currently being conducted. Our results provide some clues as to Y-sequence conservation across species and demonstrate the limitations of FISH across species with total DNA sequences from a particular chromosome.

  15. Chromosomal profile of indigenous pig (Sus scrofa

    Directory of Open Access Journals (Sweden)

    P. Guru Vishnu

    2015-02-01

    Full Text Available Aim: The objective of this study was to investigate the chromosomal profile of indigenous pigs by computing morphometric measurements. Materials and Methods: A cytogenetic study was carried out in 60 indigenous pigs to analyze the chromosomal profile by employing the short term peripheral blood lymphocyte culture technique. Results: The modal chromosome number (2n in indigenous pigs was found to be 38 and a fundamental number of 64 as in the exotic. First chromosome was the longest pair, and thirteenth pair was the second largest while Y-chromosome was the smallest in the karyotype of the pig. The mean relative length, arm ratio, centromeric indices and morphological indices of chromosomes varied from 1.99±0.01 to 11.23±0.09, 1.04±0.05 to 2.95±0.02, 0.51±0.14 to 0.75±0.09 and 2.08±0.07 to 8.08±0.15%, respectively in indigenous pigs. Sex had no significant effect (p>0.05 on all the morphometric measurements studied. Conclusion: The present study revealed that among autosomes first five pairs were sub metacentric, next two pairs were sub telocentric (6-7, subsequent five pairs were metacentric (8-12 and remaining six pairs were telocentric (13-18, while both allosomes were metacentric. The chromosomal number, morphology and various morphometric measurements of the chromosomes of the indigenous pigs were almost similar to those established breeds reported in the literature.

  16. Die Haplotypisierung des Y-Chromosoms

    OpenAIRE

    Roewer, Lutz

    2001-01-01

    Haploid vererbte Polymorphismen des Y-Chromosoms sind wichtige diagnostische Werkzeuge der forensischen Genetik und verwandter Disziplinen, insbesondere der Anthropologie. Geschlechtsspezifität und uniparentaler Erbgang der Merkmale ermöglichen eine Reihe von Untersuchungen, die mit autosomalen Markern erfolglos bleiben müssen. Kurze tandem-repetitive STR-Sequenzen, die polymorphen Marker der Wahl im forensischen Labor, sind auch auf dem Y-Chromosom nachzuweisen. Aufgrund der rekombinationsfr...

  17. A comparison of on-axis and off-axis heliostat alignment strategies

    Energy Technology Data Exchange (ETDEWEB)

    Jones, S.A.

    1996-03-01

    Heliostat installation and alignment costs will be an important element in future solar power tower projects. The predicted annual performances of on- and-off axis strategies are compared for 95 m{sup 2} flat-glass heliostats and an external, molten-salt receiver. Actual approaches to heliostat alignment that have been used in the past are briefly discussed, and relative strengths and limitations are noted. The optimal approach can vary with the application.

  18. Suicidal events among pathological gamblers: the role of comorbidity of axis I and axis II disorders.

    Science.gov (United States)

    Bischof, Anja; Meyer, Christian; Bischof, Gallus; John, Ulrich; Wurst, Friedrich Martin; Thon, Natasha; Lucht, Michael; Grabe, Hans Joergen; Rumpf, Hans-Juergen

    2015-02-28

    The risk for suicidal ideation and suicide attempts among pathological gamblers is high compared to the general population. Little is known about the interplay of Axis I and Axis II disorders, severity of gambling disorder, and suicidal ideation and suicide attempts. The study aims to address this linkage. The sampling design of the study "Pathological Gambling and Epidemiology" (PAGE) included four recruitment channels: general population, gambling locations, project telephone hotline, and in-patient treatment for pathological gambling. A total of 442 study participants with lifetime pathological gambling received a clinical interview. The multivariate analysis showed mood disorders (Relative Risk Ratio, RRR=5.14, 95%-Confidence Interval, CI=2.91-9.07), substance use disorders (RRR=1.73, CI=1.02-2.94), and early onset of gambling disorder (RRR=0.96, CI=0.93-0.99) to be associated with suicidal ideation. Suicidal attempts were associated with female sex (RRR=3.58, CI=1.56-8.19), mood disorders (RRR=11.92, CI=4.70-30.26), and Cluster B personality disorders (RRR=2.40, CI=1.13-5.10). Among study participants with suicide attempts, more had a Cluster B personality disorder than among participants with ideation solely (RRR=3.08, CI=1.48-6.40). Among this large mixed sample of pathological gamblers, high proportions of individuals with suicidal events, multi-morbidity on Axis I, and a strong linkage to Cluster B personality disorders were found. PMID:25537488

  19. The X chromosome of monotremes shares a highly conserved region with the eutherian and marsupial X chromosomes despite the absence of X chromosome inactivation.

    OpenAIRE

    Watson, J M; Spencer, J. A.; Riggs, A D; Graves, J.A.

    1990-01-01

    Eight genes, located on the long arm of the human X chromosome and present on the marsupial X chromosome, were mapped by in situ hybridization to the chromosomes of the platypus Ornithorhynchus anatinus, one of the three species of monotreme mammals. All were located on the X chromosome. We conclude that the long arm of the human X chromosome represents a highly conserved region that formed part of the X chromosome in a mammalian ancestor at least 150 million years ago. Since three of these g...

  20. Characterizing the chromosomes of the platypus (Ornithorhynchus anatinus).

    Science.gov (United States)

    McMillan, Daniel; Miethke, Pat; Alsop, Amber E; Rens, Willem; O'Brien, Patricia; Trifonov, Vladimir; Veyrunes, Frederic; Schatzkamer, Kyriena; Kremitzki, Colin L; Graves, Tina; Warren, Wesley; Grützner, Frank; Ferguson-Smith, Malcolm A; Graves, Jennifer A Marshall

    2007-01-01

    Like the unique platypus itself, the platypus genome is extraordinary because of its complex sex chromosome system, and is controversial because of difficulties in identification of small autosomes and sex chromosomes. A 6-fold shotgun sequence of the platypus genome is now available and is being assembled with the help of physical mapping. It is therefore essential to characterize the chromosomes and resolve the ambiguities and inconsistencies in identifying autosomes and sex chromosomes. We have used chromosome paints and DAPI banding to identify and classify pairs of autosomes and sex chromosomes. We have established an agreed nomenclature and identified anchor BAC clones for each chromosome that will ensure unambiguous gene localizations. PMID:18185982

  1. Chromosomal variations in the primate Alouatta seniculus seniculus.

    Science.gov (United States)

    Yunis, E J; Torres de Caballero, O M; Ramírez, C; Ramírez, Z E

    1976-01-01

    Chromosome analysis in 23 specimens of Alouatta s. seniculus trapped in different localities of Colombia were examined with the C- and Q-banding techniques. The chromosome numbers (2n=44) showed variations from 2n = 43 to 2n = 45 involving three and five microchromosomes, respectively. Two specimens also showed a structural chromosome variation involving a pericentric inversion of the chromosome No. 13. Chromosome measurements revealed an X chromosome with a value significantly smaller to that established for the standard mammalian X chromosome. PMID:817992

  2. Evolutionary stability of sex chromosomes in snakes.

    Science.gov (United States)

    Rovatsos, Michail; Vukić, Jasna; Lymberakis, Petros; Kratochvíl, Lukáš

    2015-12-22

    Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. PMID:26702042

  3. Origin and evolution of X chromosome inactivation.

    Science.gov (United States)

    Gribnau, Joost; Grootegoed, J Anton

    2012-06-01

    Evolution of the mammalian sex chromosomes heavily impacts on the expression of X-encoded genes, both in marsupials and placental mammals. The loss of genes from the Y chromosome forced a two-fold upregulation of dose sensitive X-linked homologues. As a corollary, female cells would experience a lethal dose of X-linked genes, if this upregulation was not counteracted by evolution of X chromosome inactivation (XCI) that allows for only one active X chromosome per diploid genome. Marsupials rely on imprinted XCI, which inactivates always the paternally inherited X chromosome. In placental mammals, random XCI (rXCI) is the predominant form, inactivating either the maternal or paternal X. In this review, we discuss recent new insights in the regulation of XCI. Based on these findings, we propose an X inactivation center (Xic), composed of a cis-Xic and trans-Xic that encompass all elements and factors acting to control rXCI either in cis or in trans. We also highlight that XCI may have evolved from a very small nucleation site on the X chromosome in the vicinity of the Sox3 gene. Finally, we discuss the possible evolutionary road maps that resulted in imprinted XCI and rXCI as observed in present day mammals. PMID:22425180

  4. Iklan pada Provider AXIS dan TELKOMSEL di Televisi

    OpenAIRE

    Simatupang, Perdana Tua

    2015-01-01

    Perdana Tua Simatupang. Communication Science. The title of the study is “AXIS and TELKOMSEL provider Television Commercial”. The goal of this study is to see the communication advertisement by AXIS and TELKOMSEL provider through television commercial. This study is using communication advertising theory and television commercial theory. Analysis used is single table data analysis and analytic hierarchy process(AHP). The object of the study is AXIS provider television commercial “Group Hug” v...

  5. Analysis and design of a vertical axis wind turbine

    OpenAIRE

    Goyena Iriso, Joseba

    2011-01-01

    The main objective of this project is to design a new vertical axis wind turbine, specifically one Giromill wind turbine. The project development requires performing a previous study of the vertical axis wind turbines currently development. This study has to be performed before starting to design the wind turbine. Other very important aim is the development of a new vertical axis wind turbine. The after analyses that will result in the final design of the wind turbine will b...

  6. Energy Efficient Hybrid Dual Axis Solar Tracking System

    OpenAIRE

    Rashid Ahammed Ferdaus; Mahir Asif Mohammed; Sanzidur Rahman; Sayedus Salehin; Mohammad Abdul Mannan

    2014-01-01

    This paper describes the design and implementation of an energy efficient solar tracking system from a normal mechanical single axis to a hybrid dual axis. For optimizing the solar tracking mechanism electromechanical systems were evolved through implementation of different evolutional algorithms and methodologies. To present the tracker, a hybrid dual-axis solar tracking system is designed, built, and tested based on both the solar map and light sensor based continuous tracking mechanism. Th...

  7. Semiactive Vibration Control for Horizontal Axis Washing Machine

    OpenAIRE

    Barış Can Yalçın; Haluk Erol

    2015-01-01

    A semiactive vibration control method is developed to cope with the dynamic stability problem of a horizontal axis washing machine. This method is based on adjusting the maximum force values produced by the semiactive suspension elements considering a washing machine’s vibration data (three axis angular position and three axis angular acceleration values in time). Before actuation signals are received by the step motors of the friction dampers, vibration data are evaluated, and then, the step...

  8. Piperine alleviates osteoclast formation through the p38/c-Fos/NFATc1 signaling axis.

    Science.gov (United States)

    Deepak, Vishwa; Kruger, Marlena C; Joubert, Annie; Coetzee, Magdalena

    2015-01-01

    Increased bone fracture is one of the health risk factors in patients with bone loss related disorders such as osteoporosis and breast cancer metastasis to bone. Over activity of osteoclasts leads to uncoupling of bone remodeling favoring bone loss over bone formation. Receptor activator of nuclear factor-κβ ligand (RANKL) triggers the differentiation pathway leading to multinucleated osteoclast formation. Modulation of RANKL or its downstream signaling pathways involved in osteoclast formation is of significant interest in the development of anti-resorptive agents. In this study, the effects of piperine, an alkaloid present in Piper nigrum L. on osteoclast formation was investigated. Piperine inhibited tartrate-resistant acid phosphatase-positive multinucleated osteoclast formation in murine RAW264.7 macrophages and human CD14+ monocytes induced by RANKL and breast cancer cells. Piperine attenuated the p38-mitogen activated protein kinase pathway activation, while the extracellular-signal-regulated kinase, c-Jun N-terminal kinase, or NF-κβ pathways downstream of RANKL remained unaffected. Concomitantly, expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), the key transcription factors involved in osteoclastogenesis were remarkably inhibited by piperine. Furthermore, piperine disrupted the actin ring structure and bone resorption, a characteristic hallmark of osteoclasts. Collectively, these results suggested that piperine inhibited osteoclast differentiation by suppressing the p38/NFATc1/c-Fos signaling axis.. PMID:26627060

  9. The multi-axis vibration environment and man.

    Science.gov (United States)

    Lovesey, E J

    1970-12-01

    Many investigations into the effects of vibration on man have been performed since Mallock's first study of London Underground vibrations in 1902. The vibration research has tended to be confined to the vertical (heave) axis, yet recent experiments have indicated that low frequency vibration along the lateral (sway) axis has a greater adverse effect upon comfort and performance. Measurements of the vibration environments in current forms of transport including motor vehicles, hovercraft and aircraft etc have shown that appreciable quantities of vibration along all three axes exist. Further vibration research should consider the effects of multi-axis vibrations upon man rather than limit tests to single axis vibration. PMID:15676336

  10. Neuroactive steroids and stress axis regulation: Pregnancy and beyond.

    Science.gov (United States)

    Brunton, Paula J

    2016-06-01

    The hypothalamo-pituitary-adrenal (HPA) axis plays a critical role in regulating responses to stress and long term dysregulation of the HPA axis is associated with higher rates of mood disorders. There are circumstances where the HPA axis is more or less responsive to stress. For example, during late pregnancy ACTH and corticosterone responses to stress are markedly suppressed, whereas in offspring born to mothers that experienced repeated stress during pregnancy, the HPA axis is hyper-responsive to stress. Neuroactive steroids such as allopregnanolone, tetrahydrodeoxycorticosterone (THDOC) and androstanediol can modulate HPA axis activity and concentrations of some neuroactive steroids in the brain are altered during pregnancy and following stress. Thus, here altered neurosteroidogenesis is proposed as a mechanism that could underpin the dynamic changes in HPA axis regulation typically observed in late pregnant and in prenatally stressed individuals. In support of this hypothesis, evidence in rats demonstrates that elevated levels of allopregnanolone in pregnancy induce a central inhibitory opioid mechanism that serves to minimize stress-induced HPA axis activity. Conversely, in prenatally stressed rodents, where HPA axis stress responses are enhanced, evidence indicates the capacity of the brain for neurosteroidogenesis is reduced. Understanding the mechanisms involved in adaptations in HPA axis regulation may provide insights for manipulating stress sensitivity and for developing therapies for stress-related disorders in humans. PMID:26259885

  11. Comparison of long-axis and short-axis PROPELLER-EPI for diffusion-weighted magnetic resonance imaging; Vergleich von Long-Axis- und Short-Axis-PROPELLER-EPI fuer die diffusionsgewichtete Magnetresonanztomographie

    Energy Technology Data Exchange (ETDEWEB)

    Rossbach, Matthias; Jochimsen, Thies H.; Herrmann, Karl-Heinz; Ros, Christian; Guellmar, Daniel; Reichenbach, Juergen R. [Jena Univ. Hospital (Germany). Medical Physics Group

    2011-07-01

    Echo planar imaging (EPI) in combination with PROPELLER allows high-resolution diffusion-weighted imaging. In this study, the image quality of short-axis and long-axis PROPELLER was compared and optimized using phantom and in vivo data. Furthermore, diffusion-weighted measurements using both sequences were compared with those of a reference sequence. It was found that the long-axis sequence provided better image quality, whereas the results of the diffusion weighted measurements were more accurate with the short-axis variant, and that the results of the diffusion weighted measurements of both sequences agreed well with those of the reference sequence. (orig.)

  12. Microbiota and the gut-brain axis.

    Science.gov (United States)

    Bienenstock, John; Kunze, Wolfgang; Forsythe, Paul

    2015-08-01

    Changes in gut microbiota can modulate the peripheral and central nervous systems, resulting in altered brain functioning, and suggesting the existence of a microbiota gut-brain axis. Diet can also change the profile of gut microbiota and, thereby, behavior. Effects of bacteria on the nervous system cannot be disassociated from effects on the immune system since the two are in constant bidirectional communication. While the composition of the gut microbiota varies greatly among individuals, alterations to the balance and content of common gut microbes may affect the production of molecules such as neurotransmitters, e.g., gamma amino butyric acid, and the products of fermentation, e.g., the short chain fatty acids butyrate, propionate, and acetate. Short chain fatty acids, which are pleomorphic, especially butyrate, positively influence host metabolism by promoting glucose and energy homeostasis, regulating immune responses and epithelial cell growth, and promoting the functioning of the central and peripheral nervous systems. In the future, the composition, diversity, and function of specific probiotics, coupled with similar, more detailed knowledge about gut microbiota, will potentially help in developing more effective diet- and drug-based therapies. PMID:26175487

  13. Yaw dynamics of horizontal axis wind turbines

    Science.gov (United States)

    Hansen, A. C.

    1992-05-01

    Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw-controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they know they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cost savings and reliability improvement. The risk of a yaw-free system could be minimized if methods were available for analyzing and understanding yaw behavior. The complexity of yaw behavior has, until recently, discouraged engineers from developing a complete yaw analysis method. The objectives of this work are to (1) provide a fundamental understanding of free-yaw mechanics and the design concepts most effective at eliminating yaw problems, and (2) provide tested design tools and guidelines for use by free-yaw wind systems manufacturers. The emphasis is on developing practical and sufficiently accurate design methods.

  14. Yaw dynamics of horizontal axis wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.C. (Utah Univ., Salt Lake City, UT (United States))

    1992-05-01

    Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw- controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they known they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cost savings and reliability improvement. The risk of a yaw-free system could be minimized if methods were available for analyzing and understanding yaw behavior. The complexity of yaw behavior has, until recently, discouraged engineers from developing a complete yaw analysis method. The objectives of this work are to (1) provide a fundamental understanding of free-yaw mechanics and the design concepts most effective at eliminating yaw problems, and (2) provide tested design tools and guidelines for use by free-yaw wind systems manufacturers. The emphasis is on developing practical and sufficiently accurate design methods.

  15. Localization of ecdysterone on polytene chromosomes of Drosophila melanogaster.

    OpenAIRE

    Gronemeyer, H; Pongs, O

    1980-01-01

    Ecdysterone has been crosslinked in situ to polytene chromosomes of salivary glands of Drosophila melanogaster by photoactivation. The crosslinked hormone has been localized on the chromosomes by indirect immunofluorescence microscopy. At different developmental stages the hormone was detected at different chromosomal loci. These chromosomal sites correspond to ecdysterone-inducible puff sites. Thus, the hormone binds directly to chromosomal loci, whose transcription depends on the presence o...

  16. Induction of vascular remodeling in the lung by chronic house dust mite exposure.

    Science.gov (United States)

    Rydell-Törmänen, Kristina; Johnson, Jill R; Fattouh, Ramzi; Jordana, Manel; Erjefält, Jonas S

    2008-07-01

    Structural changes to the lung are associated with chronic asthma. In addition to alterations to the airway wall, asthma is associated with vascular modifications, although this aspect of remodeling is poorly understood. We sought to evaluate the character and kinetics of vascular remodeling in response to chronic aeroallergen exposure. Because many ovalbumin-driven models used to investigate allergic airway disease do so in the absence of persistent airway inflammation, we used a protocol of chronic respiratory exposure to house dust mite extract (HDME), which has been shown to induce persistent airway inflammation consistent with that seen in humans with asthma. Mice were exposed to HDME intranasally for 7 or 20 consecutive weeks, and resolution of the inflammatory and remodeling response to allergen was investigated 4 weeks after the end of a 7-week exposure protocol. Measures of vascular remodeling, including total collagen deposition, procollagen I production, endothelial and smooth muscle cell proliferation, smooth muscle area, and presence of myofibroblasts, were investigated histologically in lung vessels of different sizes and locations. We observed an increase in total collagen content, which did not resolve upon cessation of allergen exposure. Other parameters were significantly increased after 7 and/or 20 weeks of allergen exposure but returned to baseline after allergen withdrawal. We conclude that respiratory HDME exposure induces airway remodeling and pulmonary vascular remodeling, and, in accordance with airway remodeling, some components of these structural changes may be irreversible. PMID:18314535

  17. Genome-wide analysis of interactions between ATP-dependent chromatin remodeling and histone modifications

    Directory of Open Access Journals (Sweden)

    Wang Jiang

    2009-07-01

    Full Text Available Abstract Background ATP-dependent chromatin remodeling and the covalent modification of histones play central roles in determining chromatin structure and function. Although several specific interactions between these two activities have been elaborated, the global landscape remains to be elucidated. Results In this paper, we have developed a computational method to generate the first genome-wide landscape of interactions between ATP-dependent chromatin remodeling and the covalent modification of histones in Saccharomyces cerevisiae. Our method succeeds in identifying known interactions and uncovers many previously unknown interactions between these two activities. Analysis of the genome-wide picture revealed that transcription-related modifications tend to interact with more chromatin remodelers. Our results also demonstrate that most chromatin remodeling-modification interactions act via interactions of remodelers with both histone-modifying enzymes and histone residues. We also found that the co-occurrence of both modification and remodeling has significantly different influences on multiple gene features (e.g. nucleosome occupancy compared with the presence of either one. Conclusion We gave the first genome-wide picture of ATP-dependent chromatin remodeling-histone modification interactions. We also revealed how these two activities work together to regulate chromatin structure and function. Our results suggest that distinct strategies for regulating chromatin activity are selectively employed by genes with different properties.

  18. Remodeling of nuclear architecture by the thiodioxoxpiperazine metabolite chaetocin

    International Nuclear Information System (INIS)

    Extensive changes of higher order chromatin arrangements can be observed during prometaphase, terminal cell differentiation and cellular senescence. Experimental systems where major reorganization of nuclear architecture can be induced under defined conditions, may help to better understand the functional implications of such changes. Here, we report on profound chromatin reorganization in fibroblast nuclei by chaetocin, a thiodioxopiperazine metabolite. Chaetocin induces strong condensation of chromosome territories separated by a wide interchromatin space largely void of DNA. Cell viability is maintained irrespective of this peculiar chromatin phenotype. Cell cycle markers, histone signatures, and tests for cellular senescence and for oxidative stress indicate that chaetocin induced chromatin condensation/clustering (CICC) represents a distinct entity among nuclear phenotypes associated with condensed chromatin. The territorial organization of entire chromosomes is maintained in CICC nuclei; however, the conventional nuclear architecture harboring gene-dense chromatin in the nuclear interior and gene-poor chromatin at the nuclear periphery is lost. Instead gene-dense and transcriptionally active chromatin is shifted to the periphery of individual condensed chromosome territories where nascent RNA becomes highly enriched around their outer surface. This chromatin reorganization makes CICC nuclei an attractive model system to study this border zone as a distinct compartment for transcription. Induction of CICC is fully inhibited by thiol-dependent antioxidants, but is not related to the production of reactive oxygen species. Our results suggest that chaetocin functionally impairs the thioredoxin (Trx) system, which is essential for deoxynucleotide synthesis, but in addition involved in a wide range of cellular functions. The mechanisms involved in CICC formation remain to be fully explored.

  19. Disruption of TGF-β signaling in smooth muscle cell prevents flow-induced vascular remodeling

    International Nuclear Information System (INIS)

    Highlights: • TGF-β signaling in SMC contributes to the flow-induced vascular remodeling. • Disruption of TGF-β signaling in SMC can prevent this process. • Targeting SM-specific Tgfbr2 could be a novel therapeutic strategy for vascular remodeling. - Abstract: Transforming growth factor-β (TGF-β) signaling has been prominently implicated in the pathogenesis of vascular remodeling, especially the initiation and progression of flow-induced vascular remodeling. Smooth muscle cells (SMCs) are the principal resident cells in arterial wall and are critical for arterial remodeling. However, the role of TGF-β signaling in SMC for flow-induced vascular remodeling remains unknown. Therefore, the goal of our study was to determine the effect of TGF-β pathway in SMC for vascular remodeling, by using a genetical smooth muscle-specific (SM-specific) TGF-β type II receptor (Tgfbr2) deletion mice model. Mice deficient in the expression of Tgfbr2 (MyhCre.Tgfbr2f/f) and their corresponding wild-type background mice (MyhCre.Tgfbr2WT/WT) underwent partial ligation of left common carotid artery for 1, 2, or 4 weeks. Then the carotid arteries were harvested and indicated that the disruption of Tgfbr2 in SMC provided prominent inhibition of vascular remodeling. And the thickening of carotid media, proliferation of SMC, infiltration of macrophage, and expression of matrix metalloproteinase (MMP) were all significantly attenuated in Tgfbr2 disruption mice. Our study demonstrated, for the first time, that the TGF-β signaling in SMC plays an essential role in flow-induced vascular remodeling and disruption can prevent this process

  20. Remodeling of ribosomal genes in somatic cells by Xenopus egg extract

    Energy Technology Data Exchange (ETDEWEB)

    Ostrup, Olga, E-mail: osvarcova@gmail.com [Institute of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Frederiksberg C (Denmark); Stem Cell Epigenetics Laboratory, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo (Norway); Norwegian Center for Stem Cell Research, Oslo (Norway); Hyttel, Poul; Klaerke, Dan A. [Institute of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Frederiksberg C (Denmark); Collas, Philippe, E-mail: philc@medisin.uio.no [Stem Cell Epigenetics Laboratory, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo (Norway); Norwegian Center for Stem Cell Research, Oslo (Norway)

    2011-09-02

    Highlights: {yields} Xenopus egg extract remodels nuclei and alter cell growth characteristics. {yields} Ribosomal genes are reprogrammed within 6 h after extract exposure. {yields} rDNA reprogramming involves promoter targeting of SNF2H remodeling complex. {yields} Xenopus egg extract does not initiate stress-related response in somatic cells. {yields} Aza-cytidine elicits a stress-induced response in reprogrammed cells. -- Abstract: Extracts from Xenopus eggs can reprogram gene expression in somatic nuclei, however little is known about the earliest processes associated with the switch in the transcriptional program. We show here that an early reprogramming event is the remodeling of ribosomal chromatin and gene expression. This occurs within hours of extract treatment and is distinct from a stress response. Egg extract elicits remodeling of the nuclear envelope, chromatin and nucleolus. Nucleolar remodeling involves a rapid and stable decrease in ribosomal gene transcription, and promoter targeting of the nucleolar remodeling complex component SNF2H without affecting occupancy of the transcription factor UBF and the stress silencers SUV39H1 and SIRT1. During this process, nucleolar localization of UBF and SIRT1 is not altered. On contrary, azacytidine pre-treatment has an adverse effect on rDNA remodeling induced by extract and elicits a stress-type nuclear response. Thus, an early event of Xenopus egg extract-mediated nuclear reprogramming is the remodeling of ribosomal genes involving nucleolar remodeling complex. Condition-specific and rapid silencing of ribosomal genes may serve as a sensitive marker for evaluation of various reprogramming methods.