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Sample records for crest progenitors endowed

  1. The number of fetal nephron progenitor cells limits ureteric branching and adult nephron endowment.

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    Cebrian, Cristina; Asai, Naoya; D'Agati, Vivette; Costantini, Frank

    2014-04-10

    Nephrons, the functional units of the kidney, develop from progenitor cells (cap mesenchyme [CM]) surrounding the epithelial ureteric bud (UB) tips. Reciprocal signaling between UB and CM induces nephrogenesis and UB branching. Although low nephron number is implicated in hypertension and renal disease, the mechanisms that determine nephron number are obscure. To test the importance of nephron progenitor cell number, we genetically ablated 40% of these cells, asking whether this would limit kidney size and nephron number or whether compensatory mechanisms would allow the developing organ to recover. The reduction in CM cell number decreased the rate of branching, which in turn allowed the number of CM cells per UB tip to normalize, revealing a self-correction mechanism. However, the retarded UB branching impaired kidney growth, leaving a permanent nephron deficit. Thus, the number of fetal nephron progenitor cells is an important determinant of nephron endowment, largely via its effect on UB branching.

  2. Adipose stromal cells contain phenotypically distinct adipogenic progenitors derived from neural crest.

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    Yoshihiro Sowa

    Full Text Available Recent studies have shown that adipose-derived stromal/stem cells (ASCs contain phenotypically and functionally heterogeneous subpopulations of cells, but their developmental origin and their relative differentiation potential remain elusive. In the present study, we aimed at investigating how and to what extent the neural crest contributes to ASCs using Cre-loxP-mediated fate mapping. ASCs harvested from subcutaneous fat depots of either adult P0-Cre/or Wnt1-Cre/Floxed-reporter mice contained a few neural crest-derived ASCs (NCDASCs. This subpopulation of cells was successfully expanded in vitro under standard culture conditions and their growth rate was comparable to non-neural crest derivatives. Although NCDASCs were positive for several mesenchymal stem cell markers as non-neural crest derivatives, they exhibited a unique bipolar or multipolar morphology with higher expression of markers for both neural crest progenitors (p75NTR, Nestin, and Sox2 and preadipocytes (CD24, CD34, S100, Pref-1, GATA2, and C/EBP-delta. NCDASCs were able to differentiate into adipocytes with high efficiency but their osteogenic and chondrogenic potential was markedly attenuated, indicating their commitment to adipogenesis. In vivo, a very small proportion of adipocytes were originated from the neural crest. In addition, p75NTR-positive neural crest-derived cells were identified along the vessels within the subcutaneous adipose tissue, but they were negative for mural and endothelial markers. These results demonstrate that ASCs contain neural crest-derived adipocyte-restricted progenitors whose phenotype is distinct from that of non-neural crest derivatives.

  3. Defining properties of neural crest-derived progenitor cells from the apex of human developing tooth.

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    Degistirici, Ozer; Jaquiery, Claude; Schönebeck, Bodo; Siemonsmeier, Jürgen; Götz, Werner; Martin, Ivan; Thie, Michael

    2008-02-01

    The connective tissue of the human tooth arises from cells that are derived from the cranial neural crest and, thus, are termed as "ectomesenchymal cells." Here, cells being located in a pad-like tissue adjacent to the apex of the developing tooth, which we designated the third molar pad, were separated by the microexplant technique. When outgrowing from the explant, dental neural crest-derived progenitor cells (dNC-PCs) adhered to plastic, proliferated steadily, and displayed a fibroblast-like morphology. At the mRNA level, dNC-PCs expressed neural crest marker genes like Sox9, Snail1, Snail2, Twist1, Msx2, and Dlx6. Cytofluorometric analysis indicated that cells were positive for CD49d (alpha4 integrin), CD56 (NCAM), and PDGFRalpha, while negative for CD31, CD34, CD45, and STRO-1. dNC-PCs could be differentiated into neurogenic, chondrogenic, and osteogenic lineages and were shown to produce bone matrix in athymic mice. These results demonstrate that human third molar pad possesses neural crest-derived cells that represent multipotent stem/progenitor cells. As a rather large amount of dNC-PCs could be obtained from each single third molar, cells may be used to regenerate a wide range of tissues within the craniofacial region of humans.

  4. Using human neural crest-derived progenitor cells to investigate osteogenesis: an in vitro study.

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    Degistirici, Ozer; Grabellus, Florian; Irsen, Stephan; Schmid, Kurt Werner; Thie, Michael

    2010-04-01

    Human tooth contains a distinct population of neural crest-derived progenitor cells (dNC-PCs) which are known to give rise to specialized daughter cells of an osteogenic lineage. We hypothesised that dNC-PCs could develop into neural crest-derived bone in a self-propagating and extracorporal culture system. Thus, we examined the three-dimensional structure obtained from osteogenic-stimulated dNC-PCs by morphological, biochemical and spectroscopic methods. After the onset of stimulation, cells formed a multilayer with outer cells covering the surface and inner cells secreting a hyaline matrix. With prolonged culture, multilayers contracted and formed a three-dimensional construct which subsequently converted to a calcified mass. Differentiation of progenitor cells was associated with apoptosis. Cell types which survived were smooth muscle actin-positive cells and bone-like cells. The expression of osteoblastic markers and the secretion of a collagenous matrix indicate that the bone cells had acquired their functional phenotype. Furthermore, these cells produced and secreted membrane-bound vesicles into the newly forming matrix. Consequently, an early biomineralized extracellular matrix was found with calcium phosphate deposits being associated with the newly formed collagen matrix framework. The molar calcium-phosphorus-ratio of the mineralized collagen indicated that amorphous calcium phosphate was present within this matrix. The data suggest that stimulated cultures of dNC-PCs are able to recapitulate some processes of the early phase of osteogenesis.

  5. Inactivation of Geminin in neural crest cells affects the generation and maintenance of enteric progenitor cells, leading to enteric aganglionosis.

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    Stathopoulou, Athanasia; Natarajan, Dipa; Nikolopoulou, Pinelopi; Patmanidi, Alexandra L; Lygerou, Zoi; Pachnis, Vassilis; Taraviras, Stavros

    2016-01-15

    Neural crest cells comprise a multipotent, migratory cell population that generates a diverse array of cell and tissue types, during vertebrate development. Enteric Nervous System controls the function of the gastrointestinal tract and is mainly derived from the vagal and sacral neural crest cells. Deregulation on self-renewal and differentiation of the enteric neural crest cells is evident in enteric nervous system disorders, such as Hirschsprung disease, characterized by the absence of ganglia in a variable length of the distal bowel. Here we show that Geminin is essential for Enteric Nervous System generation as mice that lacked Geminin expression specifically in neural crest cells revealed decreased generation of vagal neural crest cells, and enteric neural crest cells (ENCCs). Geminin-deficient ENCCs showed increased apoptosis and decreased cell proliferation during the early stages of gut colonization. Furthermore, decreased number of committed ENCCs in vivo and the decreased self-renewal capacity of enteric progenitor cells in vitro, resulted in almost total aganglionosis resembling a severe case of Hirschsprung disease. Our results suggest that Geminin is an important regulator of self-renewal and survival of enteric nervous system progenitor cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Environmental factors unveil dormant developmental capacities in multipotent progenitors of the trunk neural crest.

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    Coelho-Aguiar, Juliana M; Le Douarin, Nicole M; Dupin, Elisabeth

    2013-12-01

    The neural crest (NC), an ectoderm-derived structure of the vertebrate embryo, gives rise to the melanocytes, most of the peripheral nervous system and the craniofacial mesenchymal tissues (i.e., connective, bone, cartilage and fat cells). In the trunk of Amniotes, no mesenchymal tissues are derived from the NC. In certain in vitro conditions however, avian and murine trunk NC cells (TNCCs) displayed a limited mesenchymal differentiation capacity. Whether this capacity originates from committed precursors or from multipotent TNCCs was unknown. Here, we further investigated the potential of TNCCs to develop into mesenchymal cell types in vitro. We found that, in fact, quail TNCCs exhibit a high ability to differentiate into myofibroblasts, chondrocytes, lipid-laden adipocytes and mineralizing osteoblasts. In single cell cultures, both mesenchymal and neural cell types coexisted in TNCC clonal progeny: 78% of single cells yielded osteoblasts together with glial cells and neurons; moreover, TNCCs generated heterogenous clones with adipocytes, myofibroblasts, melanocytes and/or glial cells. Therefore, alike cephalic NCCs, early migratory TNCCs comprised multipotent progenitors able to generate both mesenchymal and melanocytic/neural derivatives, suggesting a continuum in NC developmental potentials along the neural axis. The skeletogenic capacity of the TNC, which was present in the exoskeletal armor of the extinct basal forms of Vertebrates and which persisted in the distal fin rays of extant teleost fish, thus did not totally disappear during vertebrate evolution. Mesenchymal potentials of the TNC, although not fulfilled during development, are still present in a dormant state in Amniotes and can be disclosed in in vitro culture. Whether these potentials are not expressed in vivo due to the presence of inhibitory cues or to the lack of permissive factors in the trunk environment remains to be understood. © 2013 Published by Elsevier Inc.

  7. Tfap2a and Foxd3 regulate early steps in the development of the neural crest progenitor population.

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    Wang, Wen-Der; Melville, David B; Montero-Balaguer, Mercedes; Hatzopoulos, Antonis K; Knapik, Ela W

    2011-12-01

    The neural crest is a stem cell-like population exclusive to vertebrates that gives rise to many different cell types including chondrocytes, neurons and melanocytes. Arising from the neural plate border at the intersection of Wnt and Bmp signaling pathways, the complexity of neural crest gene regulatory networks has made the earliest steps of induction difficult to elucidate. Here, we report that tfap2a and foxd3 participate in neural crest induction and are necessary and sufficient for this process to proceed. Double mutant tfap2a (mont blanc, mob) and foxd3 (mother superior, mos) mob;mos zebrafish embryos completely lack all neural crest-derived tissues. Moreover, tfap2a and foxd3 are expressed during gastrulation prior to neural crest induction in distinct, complementary, domains; tfap2a is expressed in the ventral non-neural ectoderm and foxd3 in the dorsal mesendoderm and ectoderm. We further show that Bmp signaling is expanded in mob;mos embryos while expression of dkk1, a Wnt signaling inhibitor, is increased and canonical Wnt targets are suppressed. These changes in Bmp and Wnt signaling result in specific perturbations of neural crest induction rather than general defects in neural plate border or dorso-ventral patterning. foxd3 overexpression, on the other hand, enhances the ability of tfap2a to ectopically induce neural crest around the neural plate, overriding the normal neural plate border limit of the early neural crest territory. Although loss of either Tfap2a or Foxd3 alters Bmp and Wnt signaling patterns, only their combined inactivation sufficiently alters these signaling gradients to abort neural crest induction. Collectively, our results indicate that tfap2a and foxd3, in addition to their respective roles in the differentiation of neural crest derivatives, also jointly maintain the balance of Bmp and Wnt signaling in order to delineate the neural crest induction domain.

  8. Demystifying Endowments

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    Ehrenberg, Ronald G.

    2009-01-01

    Endowments of major universities such as Cornell have received much attention over the past few years. Last academic year, the U.S. Senate Finance Committee launched an investigation into the finances of universities with endowments that exceeded $500 million dollars and required all of these universities to file reports detailing their finances.…

  9. Genetic background impacts developmental potential of enteric neural crest-derived progenitors in the Sox10Dom model of Hirschsprung disease.

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    Walters, Lauren C; Cantrell, V Ashley; Weller, Kevin P; Mosher, Jack T; Southard-Smith, E Michelle

    2010-11-15

    Abnormalities in the development of enteric neural crest-derived progenitors (ENPs) that generate the enteric nervous system (ENS) can lead to aganglionosis in a variable portion of the distal gastrointestinal tract. Cumulative evidence suggests that variation of aganglionosis is due to gene interactions that modulate the ability of ENPs to populate the intestine; however, the developmental processes underlying this effect are unknown. We hypothesized that differences in enteric ganglion deficits could be attributable to the effects of genetic background on early developmental processes, including migration, proliferation, or lineage divergence. Developmental processes were investigated in congenic Sox10(Dom) mice, an established Hirschsprung disease (HSCR) model, on distinct inbred backgrounds, C57BL/6J (B6) and C3HeB/FeJ (C3Fe). Immuno-staining on whole-mount fetal gut tissue and dissociated cell suspensions was used to assess migration and proliferation. Flow cytometry utilizing the cell surface markers p75 and HNK-1 was used to isolate live ENPs for analysis of developmental potential. Frequency of ENPs was reduced in Sox10(Dom) embryos relative to wild-type embryos, but was unaffected by genetic background. Both migration and developmental potential of ENPs in Sox10(Dom) embryos were altered by inbred strain background with the most highly significant differences seen for developmental potential between strains and genotypes. In vivo imaging of fetal ENPs and postnatal ganglia demonstrates that altered lineage divergence impacts ganglia in the proximal intestine. Our analysis demonstrates that genetic background alters early ENS development and suggests that abnormalities in lineage diversification can shift the proportions of ENP populations and thus may contribute to ENS deficiencies in vivo.

  10. Face off against ROS: Tcof1/Treacle safeguards neuroepithelial cells and progenitor neural crest cells from oxidative stress during craniofacial development.

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    Sakai, Daisuke; Trainor, Paul A

    2016-09-01

    One-third of all congenital birth defects affect the head and face, and most craniofacial anomalies are considered to arise through defects in the development of cranial neural crest cells. Cranial neural crest cells give rise to the majority of craniofacial bones, cartilages and connective tissues. Therefore, understanding the events that control normal cranial neural crest and subsequent craniofacial development is important for elucidating the pathogenetic mechanisms of craniofacial anomalies and for the exploring potential therapeutic avenues for their prevention. Treacher Collins syndrome (TCS) is a congenital disorder characterized by severe craniofacial anomalies. An animal model of TCS, generated through mutation of Tcof1, the mouse (Mus musculus) homologue of the gene primarily mutated in association with TCS in humans, has recently revealed significant insights into the pathogenesis of TCS. Apoptotic elimination of neuroepithelial cells including neural crest cells is the primary cause of craniofacial defects in Tcof1 mutant embryos. However, our understanding of the mechanisms that induce tissue-specific apoptosis remains incomplete. In this review, we describe recent advances in our understanding of the pathogenesis TCS. Furthermore, we discuss the role of Tcof1 in normal embryonic development, the correlation between genetic and environmental factors on the severity of craniofacial abnormalities, and the prospect for prenatal prevention of craniofacial anomalies.

  11. Higher Education Endowments Return

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    Bahlmann, David; Walda, John D.; Sedlacek, Verne O.

    2012-01-01

    A new study of endowments by the National Association of College and University Business Officers (NACUBO) and the Commonfund Institute has brought good news to college and universities: While endowment returns dropped precipitously in fiscal year 2009 as a result of the financial crisis and accompanying slide in equity markets, they climbed to an…

  12. Largest College Endowments, 2011

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    Chronicle of Higher Education, 2012

    2012-01-01

    Of all endowments valued at more than $250-million, the UCLA Foundation had the highest rate of growth over the previous year, at 49 percent. This article presents a table of the largest college endowments in 2011. The table covers the "rank," "institution," "market value as of June 30, 2011," and "1-year change" of institutions participating in…

  13. Endowment and Education

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    Moore, John W.

    2000-05-01

    The 1998 annual report of the Research Corporation ( http://www.rescorp.org) contains fascinating reading for anyone with an interest in science education at private institutions. An article titled "The Midas Touch: Do Soaring Endowments Have Any Impact on College Science" concludes that "college science is seldom more than an incidental beneficiary of endowment resources, even when they are conspicuously plentiful." Written by Research Corporation director of communication W. Stevenson Bacon, the article reports on a survey of leading undergraduate institutions, dividing them between those with endowments above and below 300 million. The first surprise to me was that Harvard's endowment of 727,522 per full-time equivalent (FTE) student is exceeded by Grinnell's 760,404, and Yale's 612,015 per FTE student is far exceeded by Agnes Scott's 692,914 (much of it in Coca-Cola stock and somewhat restricted) and closely rivaled by Swarthmore's 608,955. Of the eleven institutions in the Research Corporation survey, seven were above 300,000 per FTE student and only four were below. Private-college endowments have soared along with a soaring stock market. The Research Corporation report asks whether this increased endowment income is helping colleges to provide improved education in the sciences. A major use of endowment income and gift funds is for construction of buildings. Seven of the eleven institutions surveyed had building programs under way or planned for the sciences, and three of the four remaining expected to stress science facilities in upcoming campaigns. In some cases new buildings are designed to support science effectively, but in others, according to Research Corporation Vice President Michael Doyle, "the building is an elegant shell without modern instrumentation or flexibility for future uses." New construction serves to make a campus attractive to prospective students who will bring in the tuition fees that support most of a college's budget. An "elegant

  14. Chinese Colleges Need More Endowment

    Institute of Scientific and Technical Information of China (English)

    杨瑞

    2014-01-01

    In this paper I talk about the importance of increased college endowments. First I will introduce the limited financial situation of current Chinese colleges. Second, I will present an analysis on the financial reports of STU and Yale. Thirdly, I will describe the current Chinese College endowment situation. In conclusion I will present four suggestions for enhancing current Chinese college endowments.

  15. Endowments: How Big and Where.

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    Andersen, Charles J.

    1991-01-01

    This research brief provides summary data on the size of endowments of U.S. colleges and universities. It notes the estimated market value of endowments, examines their growth from 1977 to 1987, contrasts data from independent institutions to those from public colleges and universities, indicates the heavy concentration of endowment in a…

  16. Islet1 derivatives in the heart are of both neural crest and second heart field origin

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    Engleka, Kurt A.; Manderfield, Lauren J.; Brust, Rachael D.; Li, Li; Cohen, Ashley; Dymecki, Susan M.; Epstein, Jonathan A.

    2012-01-01

    Rationale Islet1 (Isl1) has been proposed as a marker of cardiac progenitor cells derived from the second heart field and is utilized to identify and purify cardiac progenitors from murine and human specimens for ex vivo expansion. The use of Isl1 as a specific second heart field marker is dependent on its exclusion from other cardiac lineages such as neural crest. Objective Determine if Isl1 is expressed by cardiac neural crest. Methods and Results We used an intersectional fate-mapping system employing the RC::FrePe allele which reports dual Flpe and Cre recombination. Combining Isl11Cre/+, a SHF driver, and Wnt1::Flpe, a neural crest driver, with Rc::FrePe reveals that some Isl1 derivatives in the cardiac outflow tract derive from Wnt1-expressing neural crest progenitors. In contrast, no overlap was observed between Wnt1-derived neural crest and an alternative second heart field driver, Mef2c-AHF-Cre. Conclusions Isl1 is not restricted to second heart field progenitors in the developing heart but also labels cardiac neural crest. The intersection of Isl1 and Wnt1 lineages within the heart provides a caveat to using Isl1 as an exclusive second heart field cardiac progenitor marker and suggests that some Isl1-expressing progenitor cells derived from embryos, ES or iPS cultures may be of neural crest lineage. PMID:22394517

  17. Pax7 lineage contributions to the mammalian neural crest.

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    Barbara Murdoch

    Full Text Available Neural crest cells are vertebrate-specific multipotent cells that contribute to a variety of tissues including the peripheral nervous system, melanocytes, and craniofacial bones and cartilage. Abnormal development of the neural crest is associated with several human maladies including cleft/lip palate, aggressive cancers such as melanoma and neuroblastoma, and rare syndromes, like Waardenburg syndrome, a complex disorder involving hearing loss and pigment defects. We previously identified the transcription factor Pax7 as an early marker, and required component for neural crest development in chick embryos. In mammals, Pax7 is also thought to play a role in neural crest development, yet the precise contribution of Pax7 progenitors to the neural crest lineage has not been determined.Here we use Cre/loxP technology in double transgenic mice to fate map the Pax7 lineage in neural crest derivates. We find that Pax7 descendants contribute to multiple tissues including the cranial, cardiac and trunk neural crest, which in the cranial cartilage form a distinct regional pattern. The Pax7 lineage, like the Pax3 lineage, is additionally detected in some non-neural crest tissues, including a subset of the epithelial cells in specific organs.These results demonstrate a previously unappreciated widespread distribution of Pax7 descendants within and beyond the neural crest. They shed light regarding the regionally distinct phenotypes observed in Pax3 and Pax7 mutants, and provide a unique perspective into the potential roles of Pax7 during disease and development.

  18. Cardiovascular Development and the Colonizing Cardiac Neural Crest Lineage

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    Paige Snider

    2007-01-01

    Full Text Available Although it is well established that transgenic manipulation of mammalian neural crest-related gene expression and microsurgical removal of premigratory chicken and Xenopus embryonic cardiac neural crest progenitors results in a wide spectrum of both structural and functional congenital heart defects, the actual functional mechanism of the cardiac neural crest cells within the heart is poorly understood. Neural crest cell migration and appropriate colonization of the pharyngeal arches and outflow tract septum is thought to be highly dependent on genes that regulate cell-autonomous polarized movement (i.e., gap junctions, cadherins, and noncanonical Wnt1 pathway regulators. Once the migratory cardiac neural crest subpopulation finally reaches the heart, they have traditionally been thought to participate in septation of the common outflow tract into separate aortic and pulmonary arteries. However, several studies have suggested these colonizing neural crest cells may also play additional unexpected roles during cardiovascular development and may even contribute to a crest-derived stem cell population. Studies in both mice and chick suggest they can also enter the heart from the venous inflow as well as the usual arterial outflow region, and may contribute to the adult semilunar and atrioventricular valves as well as part of the cardiac conduction system. Furthermore, although they are not usually thought to give rise to the cardiomyocyte lineage, neural crest cells in the zebrafish (Danio rerio can contribute to the myocardium and may have different functions in a species-dependent context. Intriguingly, both ablation of chick and Xenopus premigratory neural crest cells, and a transgenic deletion of mouse neural crest cell migration or disruption of the normal mammalian neural crest gene expression profiles, disrupts ventral myocardial function and/or cardiomyocyte proliferation. Combined, this suggests that either the cardiac neural crest

  19. ENDOWMENT LIFE INSURANCE

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    Zeljko Sain

    2013-06-01

    Full Text Available The aim of the paper that treats the actuarial model of insurance in case of survival or early death is to show the actuarial methods and methodology for creating a model and an appropriate number of sub-models of the most popular form of life insurance in the world. The paper applies the scientific methodology of the deductive character based on scientific, theoretical knowledge and practical realities. Following the basic theoretical model’s determinants, which are at the beginning of the paper, the basic difference between models further in this paper was carried out according to the character of the premium to be paid. Finally, the financial repercussions of some models are presented at examples in insurance companies. The result of this paper is to show the spectrum of possible forms of capital endowment insurance which can be, without major problems, depending on the financial policy of the company, applied in actual practice. The conclusion of this paper shows the theoretical and the practical reality of this model, life insurance, and its quantitative and qualitative guidelines.

  20. Premigratory and migratory neural crest cells are multipotent in vivo

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    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental

  1. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental perspect

  2. [Phenotypic plasticity of neural crest-derived melanocytes and Schwann cells].

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    Dupin, Elisabeth

    2011-01-01

    Melanocytes, the pigmented cells of the skin, and the glial Schwann cells lining peripheral nerves are developmentally derived from an early and transient ectodermal structure of the vertebrate embryo, the neural crest, which is also at the origin of multiple neural and non-neural cell types. Besides melanocytes and neural cells of the peripheral nervous system, the neural crest cells give rise to mesenchymal cell types in the head, which form most of the craniofacial skeleton, dermis, fat tissue and vascular musculo-connective components. How such a wide diversity of differentiation fates is established during embryogenesis and is later maintained in adult tissues are among key questions in developmental and stem cell biology. The analysis of the developmental potentials of single neural crest cells cultured in vitro led to characterizing multipotent stem/progenitor cells as well as more restricted precursors in the early neural crest of avian and mammalian embryos. Data support a hierarchical model of the diversification of neural crest lineages through progressive restrictions of multipotent stem cell potentials driven by local environmental factors. In particular, melanocytes and glial Schwann cells were shown to arise from a common bipotent progenitor, which depends upon the peptide endothelin-3 for proliferation and self-renewal ability. In vivo, signaling by endothelin-3 and its receptor is also required for the early development of melanocytes and proper pigmentation of the vertebrate body. It is generally assumed that, after lineage specification and terminal differentiation, specialized cell types, like the melanocytes and Schwann cells, do not change their identity. However, this classic notion that somatic cell differentiation is a stable and irreversible process has been challenged by emerging evidence that dedifferentiation can occur in different biological systems through nuclear transfer, cell fusion, epigenetic modifications and ectopic gene

  3. Rutin increases neural crest stem cell survival against damage caused by aflatoxin B1

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    Jader Nones

    2015-09-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2015v28n4p1 The neural crest (NC corresponds to a collection of multipotent and oligopotent progenitors endowed with both neural and mesenchymal potential. The derivatives of the NC at the trunk level include neurons and glial cells of the peripheral nervous system, melanocytes, smooth muscle cells and some endocrine cells. The present work investigated, for the first time, the influence of aflatoxin B1 (AFB1 and the flavonoid rutin on the survival and proliferation of NC and NC-derived melanocytes. Quail NC cell cultures were treated with AFB1 (30 μM and/or rutin (20 μM for 6 days. Cell viability was assessed by MTT and trypan blue analyses and cell proliferation by BrdU staining. Melanocytes were identified by immunocytochemistry against the melanocyte-specific cellular marker MelEM. The AFB1 treatment decreased both NC cell viability and proliferation. The total number of MelEM-positive cells was also reduced after this treatment, an effect partially prevented by the addition of rutin. On the other hand, rutin added alone did not influence the NC cell population. Our results demonstrated that rutin increases the survival of the NC after damage caused by AFB1. However, additional studies are needed to better understand the mechanisms involved in AFB1 and rutin interactions.

  4. Current perspectives of the signaling pathways directing neural crest induction.

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    Stuhlmiller, Timothy J; García-Castro, Martín I

    2012-11-01

    The neural crest is a migratory population of embryonic cells with a tremendous potential to differentiate and contribute to nearly every organ system in the adult body. Over the past two decades, an incredible amount of research has given us a reasonable understanding of how these cells are generated. Neural crest induction involves the combinatorial input of multiple signaling pathways and transcription factors, and is thought to occur in two phases from gastrulation to neurulation. In the first phase, FGF and Wnt signaling induce NC progenitors at the border of the neural plate, activating the expression of members of the Msx, Pax, and Zic families, among others. In the second phase, BMP, Wnt, and Notch signaling maintain these progenitors and bring about the expression of definitive NC markers including Snail2, FoxD3, and Sox9/10. In recent years, additional signaling molecules and modulators of these pathways have been uncovered, creating an increasingly complex regulatory network. In this work, we provide a comprehensive review of the major signaling pathways that participate in neural crest induction, with a focus on recent developments and current perspectives. We provide a simplified model of early neural crest development and stress similarities and differences between four major model organisms: Xenopus, chick, zebrafish, and mouse.

  5. Embryonic Heart Progenitors and Cardiogenesis

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    Brade, Thomas; Pane, Luna S.; Moretti, Alessandra; Chien, Kenneth R.; Laugwitz, Karl-Ludwig

    2013-01-01

    The mammalian heart is a highly specialized organ, comprised of many different cell types arising from distinct embryonic progenitor populations during cardiogenesis. Three precursor populations have been identified to contribute to different myocytic and nonmyocytic cell lineages of the heart: cardiogenic mesoderm cells (CMC), the proepicardium (PE), and cardiac neural crest cells (CNCCs). This review will focus on molecular cues necessary for proper induction, expansion, and lineage-specific differentiation of these progenitor populations during cardiac development in vivo. Moreover, we will briefly discuss how the knowledge gained on embryonic heart progenitor biology can be used to develop novel therapeutic strategies for the management of congenital heart disease as well as for improvement of cardiac function in ischemic heart disease. PMID:24086063

  6. Two developmentally distinct populations of neural crest cells contribute to the zebrafish heart.

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    Cavanaugh, Ann M; Huang, Jie; Chen, Jau-Nian

    2015-08-15

    Cardiac neural crest cells are essential for outflow tract remodeling in animals with divided systemic and pulmonary circulatory systems, but their contributions to cardiac development in animals with a single-loop circulatory system are less clear. Here we genetically labeled neural crest cells and examined their contribution to the developing zebrafish heart. We identified two populations of neural crest cells that contribute to distinct compartments of zebrafish cardiovascular system at different developmental stages. A stream of neural crest cells migrating through pharyngeal arches 1 and 2 integrates into the myocardium of the primitive heart tube between 24 and 30 h post fertilization and gives rise to cardiomyocytes. A second wave of neural crest cells migrating along aortic arch 6 envelops the endothelium of the ventral aorta and invades the bulbus arteriosus after three days of development. Interestingly, while inhibition of FGF signaling has no effect on the integration of neural crest cells to the primitive heart tube, it prevents these cells from contributing to the outflow tract, demonstrating disparate responses of neural crest cells to FGF signaling. Furthermore, neural crest ablation in zebrafish leads to multiple cardiac defects, including reduced heart rate, defective myocardial maturation and a failure to recruit progenitor cells from the second heart field. These findings add to our understanding of the contribution of neural crest cells to the developing heart and provide insights into the requirement for these cells in cardiac maturation.

  7. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental

  8. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental perspect

  9. Endowment effects in gorillas (Gorilla gorilla).

    Science.gov (United States)

    Drayton, Lindsey A; Brosnan, Sarah F; Carrigan, Jodi; Stoinski, Tara S

    2013-11-01

    Reports of endowment effects in nonhuman primates have received considerable attention in the comparative literature in recent years. However, little is known about the mechanisms underlying these effects. Continuing to explore endowment effects across different species of primate may reveal subtle differences in behavior that can help formulate specific hypotheses about the relevant mechanisms and the social and ecological factors that have shaped them. In this study, we use a paradigm that has previously been used to test chimpanzees (Pan troglodytes) and orangutans (Pongo spp.) to explore whether western lowland gorillas (Gorilla gorilla) exhibit comparable endowment effects. We find that gorillas exhibit endowment effects when in possession of food, but not nonfood, items, and that they show a statistically stronger effect than chimpanzees but not orangutans. These findings are consistent with the hypothesis that mechanisms for endowment effects in primates may be related to inhibitory control or risk aversion.

  10. Market Collapse Weighs Heavily on College Endowments

    Science.gov (United States)

    Bluemenstyk, Goldie

    2009-01-01

    College endowments earned an average return of minus-3 percent for the 2008 fiscal year and an estimated minus-22.5 percent in the five months after that, two new reports show. More than a quarter of all institutions said they plan to draw less money from their endowment this year than they had expected to spend. After a half-decade of soaring…

  11. Neural crest stem cells: discovery, properties and potential for therapy

    Institute of Scientific and Technical Information of China (English)

    Annita Achilleos; Paul A Trainor

    2012-01-01

    Neural crest (NC) cells are a migratory cell population synonymous with vertebrate evolution.They generate a wide variety of cell and tissue types during embryonic and adult development including cartilage and bone,connective tissue,pigment and endocrine cells as well as neurons and glia amongst many others.Such incredible lineage potential combined with a limited capacity for self-renewal,which persists even into adult life,demonstrates that NC cells bear the key hallmarks of stem and progenitor cells.In this review,we describe the identification,characterization and isolation of NC stem and progenitor cells from different tissues in both embryo and adult organisms.We discuss their specific properties and their potential application in cell-based tissue and disease-specific repair.

  12. Modifying Endowment Spending Rules: Is it the Cure for Overspending?

    Science.gov (United States)

    Kaufman, Roger T.; Woglom, Geoffrey

    2005-01-01

    In this article we analyze the dynamics of endowment spending and real endowment values using rules that tie endowment spending to inflation. Numerical examples demonstrate that under a pure inflation rule, spending rates tend to drift away over time from the appropriate rate, leading to either rising or falling real endowment values. Under a…

  13. Endothelial cells regulate neural crest and second heart field morphogenesis.

    Science.gov (United States)

    Milgrom-Hoffman, Michal; Michailovici, Inbal; Ferrara, Napoleone; Zelzer, Elazar; Tzahor, Eldad

    2014-07-04

    Cardiac and craniofacial developmental programs are intricately linked during early embryogenesis, which is also reflected by a high frequency of birth defects affecting both regions. The molecular nature of the crosstalk between mesoderm and neural crest progenitors and the involvement of endothelial cells within the cardio-craniofacial field are largely unclear. Here we show in the mouse that genetic ablation of vascular endothelial growth factor receptor 2 (Flk1) in the mesoderm results in early embryonic lethality, severe deformation of the cardio-craniofacial field, lack of endothelial cells and a poorly formed vascular system. We provide evidence that endothelial cells are required for migration and survival of cranial neural crest cells and consequently for the deployment of second heart field progenitors into the cardiac outflow tract. Insights into the molecular mechanisms reveal marked reduction in Transforming growth factor beta 1 (Tgfb1) along with changes in the extracellular matrix (ECM) composition. Our collective findings in both mouse and avian models suggest that endothelial cells coordinate cardio-craniofacial morphogenesis, in part via a conserved signaling circuit regulating ECM remodeling by Tgfb1.

  14. Endothelial cells regulate neural crest and second heart field morphogenesis

    Directory of Open Access Journals (Sweden)

    Michal Milgrom-Hoffman

    2014-07-01

    Full Text Available Cardiac and craniofacial developmental programs are intricately linked during early embryogenesis, which is also reflected by a high frequency of birth defects affecting both regions. The molecular nature of the crosstalk between mesoderm and neural crest progenitors and the involvement of endothelial cells within the cardio–craniofacial field are largely unclear. Here we show in the mouse that genetic ablation of vascular endothelial growth factor receptor 2 (Flk1 in the mesoderm results in early embryonic lethality, severe deformation of the cardio–craniofacial field, lack of endothelial cells and a poorly formed vascular system. We provide evidence that endothelial cells are required for migration and survival of cranial neural crest cells and consequently for the deployment of second heart field progenitors into the cardiac outflow tract. Insights into the molecular mechanisms reveal marked reduction in Transforming growth factor beta 1 (Tgfb1 along with changes in the extracellular matrix (ECM composition. Our collective findings in both mouse and avian models suggest that endothelial cells coordinate cardio–craniofacial morphogenesis, in part via a conserved signaling circuit regulating ECM remodeling by Tgfb1.

  15. Why Real Estate Makes Sense for Endowments.

    Science.gov (United States)

    Kiser, Arthur G., Jr.

    1985-01-01

    Attributes of real estate that make it a desirable investment for institutional endowment funds include the uniqueness of each property, its function as a hedge against inflation, its function in stabilizing portfolio volatility, and the potential for income and diversification. (MSE)

  16. Endowments as a Source of Library Funds.

    Science.gov (United States)

    Kane, Frederick A.

    To obtain private endowments as a source of library funds the following needs to be done: (1) work hard with a definite goal in view; (2) plan a course of action; (3) contact those individuals whom investigations show may help; (4) search out help from newspapers, banks, radio and television stations; (5) consider the employment of a full time…

  17. Why Real Estate Makes Sense for Endowments.

    Science.gov (United States)

    Kiser, Arthur G., Jr.

    1985-01-01

    Attributes of real estate that make it a desirable investment for institutional endowment funds include the uniqueness of each property, its function as a hedge against inflation, its function in stabilizing portfolio volatility, and the potential for income and diversification. (MSE)

  18. Crested Ibis%朱鹮

    Institute of Scientific and Technical Information of China (English)

    丁长青

    2010-01-01

    @@ The Crested Ibis(Nipponia nippon,Plates Ⅰ and Ⅱ)(Ciconiiformes: Threskiomithidae)is a mediumsized wading bird,ranging in length from 57.5 to 84.0 cm,with a longish neck and legs,a red featherless face with a crested white head.Its most distinctive morphological character is the long,slender and decurved bill,perfectly adapted for probing in water and mud,or even in cracks on dry ground.The nonbreeding adult is white,with orange cinnamon tones in the tail and flight-feathers.The long bill is black with a red tip.Its red legs do not extend beyond the tail in flight(Hoyo et al.,1992).

  19. Integration of Medical Care and Endowment: A New Exploration of Endowment Mode in the Context of Population Aging

    Institute of Scientific and Technical Information of China (English)

    Xinpeng; XU; Xiaopeng; FU

    2015-01-01

    China’s aging pressure is increasingly serious. The elderly people are difficult to seek medical advice,the elderly dependency ratio is soaring,finance fails to bear such heavy load,and social endowment service pressure is also constantly increasing. Traditional endowment mode is already incapable of satisfying current endowment demands. On the basis of the population aging,this paper came up with the new endowment mode " hospital + nursing home" and analyzed its feasibility. Finally,it reached the conclusion that this endowment mode is helpful for solving problems of endowment and medical care,and alleviating the problem of population aging.

  20. The neural crest and neural crest cells: discovery and significance for theories of embryonic organization

    Indian Academy of Sciences (India)

    Brian K Hall

    2008-12-01

    The neural crest has long fascinated developmental biologists, and, increasingly over the past decades, evolutionary and evolutionary developmental biologists. The neural crest is the name given to the fold of ectoderm at the junction between neural and epidermal ectoderm in neurula-stage vertebrate embryos. In this sense, the neural crest is a morphological term akin to head fold or limb bud. This region of the dorsal neural tube consists of neural crest cells, a special population(s) of cell, that give rise to an astonishing number of cell types and to an equally astonishing number of tissues and organs. Neural crest cell contributions may be direct — providing cells — or indirect — providing a necessary, often inductive, environment in which other cells develop. The enormous range of cell types produced provides an important source of evidence of the neural crest as a germ layer, bringing the number of germ layers to four — ectoderm, endoderm, mesoderm, and neural crest. In this paper I provide a brief overview of the major phases of investigation into the neural crest and the major players involved, discuss how the origin of the neural crest relates to the origin of the nervous system in vertebrate embryos, discuss the impact on the germ-layer theory of the discovery of the neural crest and of secondary neurulation, and present evidence of the neural crest as the fourth germ layer. A companion paper (Hall, Evol. Biol. 2008) deals with the evolutionary origins of the neural crest and neural crest cells.

  1. Legal Origin,Endowment and Financial Development%Legal Origin, Endowment and Financial Development

    Institute of Scientific and Technical Information of China (English)

    张世雯

    2016-01-01

    Since the rise of the economic and financial development theory, around economic and financial development of the determinants and what financial arrangements for promoting economic growth and other issues, thus resulted in a variety of im-portant theoretical debate. This paper will Define what is meant by key terms such as legal tradition and endowment, explain the channels through which legal tradition and endowment affect financial development through talking about the relationship be-tween legal origin, initial in endowment and financial development. By comparing different legal traditions or the"Origins"be-tween the The Continental Law System and Common Law System, a comprehensive analysis of the effects of different origin of law on the financial and economic development.

  2. Design Guidelines for Low Crested Structures

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Lamberti, Alberto

    2004-01-01

    The paper presents an overview of the design guidelines for low crested structures (LCS's) to be applied in coastal protection schemes. The design guidelines are formulated as a part of the research project: Environmental Design of Low Crested Coastal Defence Structures (DELOS) within the EC 5FP ...

  3. Morbidity from iliac crest bone harvesting

    NARCIS (Netherlands)

    Kalk, WWI; Raghoebar, GM; Jansma, J; Boering, G

    1996-01-01

    Purpose: The iliac crest is the most common donor site for autogenous bone grafting in maxillofacial surgery. The aim of this study was to evaluate retrospectively the morbidity of bone harvesting from the inner table of the anterior iliac crest. Patients and Methods: Sixty-five patients were recall

  4. Neural crest contributions to the lamprey head

    Science.gov (United States)

    McCauley, David W.; Bronner-Fraser, Marianne

    2003-01-01

    The neural crest is a vertebrate-specific cell population that contributes to the facial skeleton and other derivatives. We have performed focal DiI injection into the cranial neural tube of the developing lamprey in order to follow the migratory pathways of discrete groups of cells from origin to destination and to compare neural crest migratory pathways in a basal vertebrate to those of gnathostomes. The results show that the general pathways of cranial neural crest migration are conserved throughout the vertebrates, with cells migrating in streams analogous to the mandibular and hyoid streams. Caudal branchial neural crest cells migrate ventrally as a sheet of cells from the hindbrain and super-pharyngeal region of the neural tube and form a cylinder surrounding a core of mesoderm in each pharyngeal arch, similar to that seen in zebrafish and axolotl. In addition to these similarities, we also uncovered important differences. Migration into the presumptive caudal branchial arches of the lamprey involves both rostral and caudal movements of neural crest cells that have not been described in gnathostomes, suggesting that barriers that constrain rostrocaudal movement of cranial neural crest cells may have arisen after the agnathan/gnathostome split. Accordingly, neural crest cells from a single axial level contributed to multiple arches and there was extensive mixing between populations. There was no apparent filling of neural crest derivatives in a ventral-to-dorsal order, as has been observed in higher vertebrates, nor did we find evidence of a neural crest contribution to cranial sensory ganglia. These results suggest that migratory constraints and additional neural crest derivatives arose later in gnathostome evolution.

  5. Analysis on management of philanthropic endowment in Chinese universities

    Institute of Scientific and Technical Information of China (English)

    MENG Dong-jun; WU Ying-jun; ZHANG Mei-feng

    2005-01-01

    Philanthropic endowment, along with government allocation, tuition fee and extra income, is one of the four major means for funding higher education in China. Research on philanthropic endowment is at its beginning stage, and so it is not yet well known. With a view to providing some useful information to our government, universities and society, this paper aims at making a brief analysis of the status quo and management of philanthropic endowment in Chinese universities.

  6. Cdon promotes neural crest migration by regulating N-cadherin localization.

    Science.gov (United States)

    Powell, Davalyn R; Williams, Jason S; Hernandez-Lagunas, Laura; Salcedo, Ernesto; O'Brien, Jenean H; Artinger, Kristin Bruk

    2015-11-15

    Neural crest cells (NCCs) are essential embryonic progenitor cells that are unique to vertebrates and form a remarkably complex and coordinated system of highly motile cells. Migration of NCCs occurs along specific pathways within the embryo in response to both environmental cues and cell-cell interactions within the neural crest population. Here, we demonstrate a novel role for the putative Sonic hedgehog (Shh) receptor and cell adhesion regulator, cdon, in zebrafish neural crest migration. cdon is expressed in developing premigratory NCCs but is downregulated once the cells become migratory. Knockdown of cdon results in aberrant migration of trunk NCCs: crestin positive cells can emigrate out of the neural tube but stall shortly after the initiation of migration. Live cell imaging analysis demonstrates reduced directedness of migration, increased velocity and mispositioned cell protrusions. In addition, transplantation analysis suggests that cdon is required cell-autonomously for directed NCC migration in the trunk. Interestingly, N-cadherin is mislocalized following cdon knockdown suggesting that the role of cdon in NCCs is to regulate N-cadherin localization. Our results reveal a novel role for cdon in zebrafish neural crest migration, and suggest a mechanism by which Cdon is required to localize N-cadherin to the cell membrane in migratory NCCs for directed migration.

  7. Id expression in amphioxus and lamprey highlights the role of gene cooption during neural crest evolution

    Science.gov (United States)

    Meulemans, Daniel; McCauley, David; Bronner-Fraser, Marianne

    2003-01-01

    Neural crest cells are unique to vertebrates and generate many of the adult structures that differentiate them from their closest invertebrate relatives, the cephalochordates. Id genes are robust markers of neural crest cells at all stages of development. We compared Id gene expression in amphioxus and lamprey to ask if cephalochordates deploy Id genes at the neural plate border and dorsal neural tube in a manner similar to vertebrates. Furthermore, we examined whether Id expression in these cells is a basal vertebrate trait or a derived feature of gnathostomes. We found that while expression of Id genes in the mesoderm and endoderm is conserved between amphioxus and vertebrates, expression in the lateral neural plate border and dorsal neural tube is a vertebrate novelty. Furthermore, expression of lamprey Id implies that recruitment of Id genes to these cells occurred very early in the vertebrate lineage. Based on expression in amphioxus we postulate that Id cooption conferred sensory cell progenitor-like properties upon the lateral neurectoderm, and pharyngeal mesoderm-like properties upon cranial neural crest. Amphioxus Id expression is also consistent with homology between the anterior neurectoderm of amphioxus and the presumptive placodal ectoderm of vertebrates. These observations support the idea that neural crest evolution was driven in large part by cooption of multipurpose transcriptional regulators from other tissues and cell types.

  8. Pax3 and Hippo Signaling Coordinate Melanocyte Gene Expression in Neural Crest

    Directory of Open Access Journals (Sweden)

    Lauren J. Manderfield

    2014-12-01

    Full Text Available Loss of Pax3, a developmentally regulated transcription factor expressed in premigratory neural crest, results in severe developmental defects and embryonic lethality. Although Pax3 mutations produce profound phenotypes, the intrinsic transcriptional activation exhibited by Pax3 is surprisingly modest. We postulated the existence of transcriptional coactivators that function with Pax3 to mediate developmental functions. A high-throughput screen identified the Hippo effector proteins Taz and Yap65 as Pax3 coactivators. Synergistic coactivation of target genes by Pax3-Taz/Yap65 requires DNA binding by Pax3, is Tead independent, and is regulated by Hippo kinases Mst1 and Lats2. In vivo, Pax3 and Yap65 colocalize in the nucleus of neural crest progenitors in the dorsal neural tube. Neural crest deletion of Taz and Yap65 results in embryo-lethal neural crest defects and decreased expression of the Pax3 target gene, Mitf. These results suggest that Pax3 activity is regulated by the Hippo pathway and that Pax factors are Hippo effectors.

  9. TRPM7 maintains progenitor-like features of neuroblastoma cells: implications for metastasis formation.

    Science.gov (United States)

    Middelbeek, Jeroen; Visser, Daan; Henneman, Linda; Kamermans, Alwin; Kuipers, Arthur J; Hoogerbrugge, Peter M; Jalink, Kees; van Leeuwen, Frank N

    2015-04-20

    Neuroblastoma is an embryonal tumor derived from poorly differentiated neural crest cells. Current research is aimed at identifying the molecular mechanisms that maintain the progenitor state of neuroblastoma cells and to develop novel therapeutic strategies that induce neuroblastoma cell differentiation. Mechanisms controlling neural crest development are typically dysregulated during neuroblastoma progression, and provide an appealing starting point for drug target discovery. Transcriptional programs involved in neural crest development act as a context dependent gene regulatory network. In addition to BMP, Wnt and Notch signaling, activation of developmental gene expression programs depends on the physical characteristics of the tissue microenvironment. TRPM7, a mechanically regulated TRP channel with kinase activity, was previously found essential for embryogenesis and the maintenance of undifferentiated neural crest progenitors. Hence, we hypothesized that TRPM7 may preserve progenitor-like, metastatic features of neuroblastoma cells. Using multiple neuroblastoma cell models, we demonstrate that TRPM7 expression closely associates with the migratory and metastatic properties of neuroblastoma cells in vitro and in vivo. Moreover, microarray-based expression profiling on control and TRPM7 shRNA transduced neuroblastoma cells indicates that TRPM7 controls a developmental transcriptional program involving the transcription factor SNAI2. Overall, our data indicate that TRPM7 contributes to neuroblastoma progression by maintaining progenitor-like features.

  10. Environmental cues from CNS, PNS, and ENS cells regulate CNS progenitor differentiation

    DEFF Research Database (Denmark)

    Brännvall, Karin; Corell, Mikael; Forsberg-Nilsson, Karin;

    2008-01-01

    Cellular origin and environmental cues regulate stem cell fate determination. Neuroepithelial stem cells form the central nervous system (CNS), whereas neural crest stem cells generate the peripheral (PNS) and enteric nervous system (ENS). CNS neural stem/progenitor cell (NSPC) fate determination...

  11. Stability of Low-Crested Breakwaters in Shallow Water Short Crested Waves

    DEFF Research Database (Denmark)

    Kramer, Morten Mejlhede; Burcharth, Hans Falk

    2003-01-01

    The paper presents results of 3D laboratory experiments on low-crested breakwaters. Two typical structural layouts were tested at model scale in a wave basin at Aalborg University, Denmark, to identify and quantify the influence of various hydrodynamic conditions (obliquity of short crested waves......, wave hight and wave steepness) and structural geometries (crest width and freeboard) on the stability of low-crested breakwaters. Results are given in terms of recommendations for design guidelines for structure stability. Damage parameters for the trunk and the roundhead are proposed based on analysis...

  12. Boeing Company gives again to engineering design team endowment

    OpenAIRE

    Owczarski, Mark

    2008-01-01

    In 2007 Virginia Tech's Student Engineers' Council announced the creation of an endowment to benefit student design teams at the university. During the fall semester of 2007, The Boeing Company increased the size of this endowment with a gift of $50,000 from its Global Corporate Citizenship disaster relief team budget and a second gift of $15,000 from its grants program.

  13. Colleges Leverage Large Endowments to Benefit Some Donors and Employees

    Science.gov (United States)

    Hermes, J. J.

    2008-01-01

    College endowments have beaten the market so consistently in recent years, it is not surprising that individuals would like to take advantage of that institutional wisdom to invest their own money. Increasingly, many are. A small but growing number of universities are trying to entice donors to invest their trusts alongside college endowments,…

  14. Trading experience modulates anterior insula to reduce the endowment effect.

    Science.gov (United States)

    Tong, Lester C P; Ye, Karen J; Asai, Kentaro; Ertac, Seda; List, John A; Nusbaum, Howard C; Hortaçsu, Ali

    2016-08-16

    People often demand a greater price when selling goods that they own than they would pay to purchase the same goods-a well-known economic bias called the endowment effect. The endowment effect has been found to be muted among experienced traders, but little is known about how trading experience reduces the endowment effect. We show that when selling, experienced traders exhibit lower right anterior insula activity, but no differences in nucleus accumbens or orbitofrontal activation, compared with inexperienced traders. Furthermore, insula activation mediates the effect of experience on the endowment effect. Similar results are obtained for inexperienced traders who are incentivized to gain trading experience. This finding indicates that frequent trading likely mitigates the endowment effect indirectly by modifying negative affective responses in the context of selling.

  15. Vagal neural crest cell migratory behavior: a transition between the cranial and trunk crest.

    Science.gov (United States)

    Kuo, Bryan R; Erickson, Carol A

    2011-09-01

    Migration and differentiation of cranial neural crest cells are largely controlled by environmental cues, whereas pathfinding at the trunk level is dictated by cell-autonomous molecular changes owing to early specification of the premigratory crest. Here, we investigated the migration and patterning of vagal neural crest cells. We show that (1) vagal neural crest cells exhibit some developmental bias, and (2) they take separate pathways to the heart and to the gut. Together these observations suggest that prior specification dictates initial pathway choice. However, when we challenged the vagal neural crest cells with different migratory environments, we observed that the behavior of the anterior vagal neural crest cells (somite-level 1-3) exhibit considerable migratory plasticity, whereas the posterior vagal neural crest cells (somite-level 5-7) are more restricted in their behavior. We conclude that the vagal neural crest is a transitional population that has evolved between the head and the trunk. Copyright © 2011 Wiley-Liss, Inc.

  16. Neural crest and mesoderm lineage-dependent gene expression in orofacial development.

    Science.gov (United States)

    Bhattacherjee, Vasker; Mukhopadhyay, Partha; Singh, Saurabh; Johnson, Charles; Philipose, John T; Warner, Courtney P; Greene, Robert M; Pisano, M Michele

    2007-06-01

    The present study utilizes a combination of genetic labeling/selective isolation of pluripotent embryonic progenitor cells, and oligonucleotide-based microarray technology, to delineate and compare the "molecular fingerprint" of two mesenchymal cell populations from distinct lineages in the developing embryonic orofacial region. The first branchial arches-bi-lateral tissue primordia that flank the primitive oral cavity-are populated by pluripotent mesenchymal cells from two different lineages: neural crest (neuroectoderm)- and mesoderm-derived mesenchymal cells. These cells give rise to all of the connective tissue elements (bone, cartilage, smooth and skeletal muscle, dentin) of the orofacial region (maxillary and mandibular portion), as well as neurons and glia associated with the cranial ganglia, among other tissues. In the present study, neural crest- and mesoderm-derived mesenchymal cells were selectively isolated from the first branchial arch of gestational day 9.5 mouse embryos using laser capture microdissection (LCM). The two different embryonic cell lineages were distinguished through utilization of a novel two component transgenic mouse model (Wnt1Cre/ZEG) in which the neural crest cells and their derivatives are indelibly marked (i.e., expressing enhanced green fluorescent protein, EGFP) throughout the pre- and post-natal lifespan of the organism. EGFP-labeled neural crest-derived, and non-fluorescent mesoderm-derived mesenchymal cells from the first branchial arch were visualized in frozen tissue sections from gestational day 9.5 mouse embryos and independently isolated by LCM under epifluorescence optics. RNA was extracted from the two populations of LCM-procured cells, and amplified by double-stranded cDNA synthesis and in vitro transcription. Gene expression profiles of the two progenitor cell populations were generated via hybridization of the cell-type specific cRNA samples to oligo-based GeneChip microarrays. Comparison of gene expression

  17. Generalized crested products of Markov chains

    CERN Document Server

    D'Angeli, Daniele

    2010-01-01

    We define a finite Markov chain, called generalized crested product, which naturally appears as a generalization of the first crested product of Markov chains. A complete spectral analysis is developed and the $k$-step transition probability is given. It is important to remark that this Markov chain describes a more general version of the classical Ehrenfest diffusion model. As a particular case, one gets a generalization of the classical Insect Markov chain defined on the ultrametric space. Finally, an interpretation in terms of representation group theory is given, by showing the correspondence between the spectral decomposition of the generalized crested product and the Gelfand pairs associated with the generalized wreath product of permutation groups.

  18. academic performance of less endowed high school students in the ...

    African Journals Online (AJOL)

    User

    rently available to describe the determinants of ... Keywords: Performance, less endowed, student, admission, university .... students, we point out the various paths of ad- mission ... near future. .... of educational attainment, occupation and job.

  19. Effective Factor Endowments, Trade Openness and Income Distribution in China

    OpenAIRE

    Xiaodong Lu; Guowei Cai

    2011-01-01

    This paper studies the empirical relationship among factor endowment, trade openness and individual income distribution. Using panel data, we show that factor endowment characters, to some extent, explains income gap in China. First, land and Capital intensive provinces have a more equal income distribution while human capital and labor-intensive provinces have a less equal income distribution. Second, Trade openness has a significant effect on China¡¯s income distribution; the interaction be...

  20. Division of labor during trunk neural crest development.

    Science.gov (United States)

    Gammill, Laura S; Roffers-Agarwal, Julaine

    2010-08-15

    Neural crest cells, the migratory precursors of numerous cell types including the vertebrate peripheral nervous system, arise in the dorsal neural tube and follow prescribed routes into the embryonic periphery. While the timing and location of neural crest migratory pathways has been well documented in the trunk, a comprehensive collection of signals that guides neural crest migration along these paths has only recently been established. In this review, we outline the molecular cascade of events during trunk neural crest development. After describing the sequential routes taken by trunk neural crest cells, we consider the guidance cues that pattern these neural crest trajectories. We pay particular attention to segmental neural crest development and the steps and signals that generate a metameric peripheral nervous system, attempting to reconcile conflicting observations in chick and mouse. Finally, we compare cranial and trunk neural crest development in order to highlight common themes.

  1. FGF Signaling Transforms Non-neural Ectoderm into Neural Crest

    OpenAIRE

    Yardley, Nathan; García-Castro, Martín I.

    2012-01-01

    The neural crest arises at the border between the neural plate and the adjacent non-neural ectoderm. It has been suggested that both neural and non-neural ectoderm can contribute to the neural crest. Several studies have examined the molecular mechanisms that regulate neural crest induction in neuralized tissues or the neural plate border. Here, using the chick as a model system, we address the molecular mechanisms by which non-neural ectoderm generates neural crest. We report that in respons...

  2. Structural Stability of Low-Crested Breakwaters

    DEFF Research Database (Denmark)

    Kramer, Morten

    A more and more widespread way to protect the coast against ongoing erosion is to build so called Low Crested Structures (LCS’s). Despite a large number of coast parallel LCS’s exist, the structural performance of these structures are not fully clarified. The LCS’s dealt with are coast parallel...

  3. Diversification of crested wheatgrass stands in Utah

    Science.gov (United States)

    April Hulet

    2009-01-01

    Agropyron cristatum [L.] Gaertner (crested wheatgrass) continues to be seeded on burned wildlands. Effective control methods need to be developed to convert these seedings to more diverse native plant communities. This research was designed to determine effective ways to control A. cristatum and establish native species while...

  4. The Crest Wing Wave Energy Device

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Antonishen, Michael Patrick

    This report presents the results of a continuation of an experimental study of the wave energy converting abilities of the Crest Wing wave energy converter (WEC), in the following referred to as ‘Phase 2'. The Crest Wing is a WEC that uses its movement in matching the shape of an oncoming wave...... to generate power. Model tests have been performed using scale models (length scale 1:30), provided by WaveEnergyFyn, in regular and irregular wave states that can be found in Assessment of Wave Energy Devices. Best Practice as used in Denmark (Frigaard et al., 2008). The tests were carried out at Dept....... of Civil Engineering, Aalborg University (AAU) in the 3D deep water wave tank. The displacement and force applied to a power take off system, provided by WaveEnergyFyn, were measured and used to calculate mechanical power available to the power take off....

  5. Mere exposure and the endowment effect on consumer decision making.

    Science.gov (United States)

    Tom, Gail; Nelson, Carolyn; Srzentic, Tamara; King, Ryan

    2007-03-01

    Previous researchers (e.g., J. A. Bargh, 1992, 2002) demonstrated the importance of nonconscious processes on consumer choice behavior. Using an advertisement, the authors determined the effect of two nonconscious processes--the mere exposure effect, which increases object preference by increasing consumer exposure to an object, and the endowment effect, which increases object valuation by providing consumer possession of an object--on consumer behavior. Although the mere exposure effect and endowment effect did not produce an interaction, they produced independent effects. The endowment effect increased object valuation but not object preference. The mere exposure effect increased object preference but not object valuation. Thus, at the unconscious level, an increase in object preference does not lead to an increase in object valuation, nor does an increase in object valuation lead to an increase in object preference. The authors discuss the importance of developing measures of unconscious process in advertising effectiveness.

  6. Human fetal cardiac progenitors: The role of stem cells and progenitors in the fetal and adult heart.

    Science.gov (United States)

    Bulatovic, Ivana; Månsson-Broberg, Agneta; Sylvén, Christer; Grinnemo, Karl-Henrik

    2016-02-01

    The human fetal heart is formed early during embryogenesis as a result of cell migrations, differentiation, and formative blood flow. It begins to beat around gestation day 22. Progenitor cells are derived from mesoderm (endocardium and myocardium), proepicardium (epicardium and coronary vessels), and neural crest (heart valves, outflow tract septation, and parasympathetic innervation). A variety of molecular disturbances in the factors regulating the specification and differentiation of these cells can cause congenital heart disease. This review explores the contribution of different cardiac progenitors to the embryonic heart development; the pathways and transcription factors guiding their expansion, migration, and functional differentiation; and the endogenous regenerative capacity of the adult heart including the plasticity of cardiomyocytes. Unfolding these mechanisms will become the basis for understanding the dynamics of specific congenital heart disease as well as a means to develop therapy for fetal as well as postnatal cardiac defects and heart failure.

  7. Sox2 acts as a rheostat of epithelial to mesenchymal transition during neural crest development

    Directory of Open Access Journals (Sweden)

    Nikolaos eMandalos

    2014-09-01

    Full Text Available Precise control of self-renewal and differentiation of progenitor cells into the cranial neural crest (CNC pool ensures proper head development, guided by signaling pathways such as BMPs, FGFs, Shh and Notch. Here, we show that murine Sox2 plays an essential role in controlling progenitor cell behavior during craniofacial development. A Conditional by Inversion Sox2 allele (Sox2COIN has been employed to generate an epiblast ablation of Sox2 function (Sox2EpINV. Sox2EpINV/+(H haploinsufficient and conditional (Sox2EpINV/mosaic mutant embryos proceed beyond gastrulation and die around E11. These mutant embryos exhibit severe anterior malformations, with hydrocephaly and frontonasal truncations, which could be attributed to the deregulation of CNC progenitor cells during their epithelial to mesenchymal transition. This irregularity results in an exacerbated and aberrant migration of Sox10+ NCC in the branchial arches and frontonasal process of the Sox2 mutant embryos. These results suggest a novel role for Sox2 as a regulator of the epithelial to mesenchymal transitions that are important for the cell flow in the developing head.

  8. Strategies for establishing an endowed chair in a service setting.

    Science.gov (United States)

    Randhawa, Simmy; Robinson, Nellie C; Feetham, Suzanne; Church, Tracy; Hinds, Pamela S; Talley, Linda B; Williams, Catherine

    2014-01-01

    To advance care for patients and families requires that providers and administrators in clinical settings place a high priority on the scientific domain of nursing. New knowledge intended to benefit nursing care is most effectively and efficiently achieved when a vibrant and well-supported nursing research program is embedded within a health care system. An endowed chair in nursing research is an esteemed strategy acknowledging the contributions of nursing science, providing credibility to a researcher and research programs, and demonstrating commitment to the infrastructure for nursing research. Organizational readiness through leadership; systems thinking; relationship development; and knowledge of the dynamics, process, and expectations of philanthropy are essential to establishing an endowed chair. Philanthropic endeavors can be used to strategically develop a high-impact campaign that resonates across public and private sectors to secure funding to solidify and advance nursing research. By actively engaging stakeholders including system leaders, frontline nurses, and other care providers and development leaders, a successful campaign can establish and sustain an endowed chair in nursing research. This article describes the stakeholders, processes, structure, and outcomes for the first endowed chair in nursing research at Children's National Health System in Washington, DC.

  9. Talent "and" Expertise: The Empirical Evidence for Genetic Endowment

    Science.gov (United States)

    Simonton, Dean Keith

    2007-01-01

    In this commentary, the author focuses on the claim summarized in the last sentence of the target article's abstract. To begin, the concept of talent does not require the existence of "innate constraints to the attainment of elite achievement". On the contrary, genetic endowment may merely influence the rate at which domain-specific expertise is…

  10. As Endowment Values Plummet, Some Institutions Consider Suing Brokers

    Science.gov (United States)

    Masterson, Kathryn

    2008-01-01

    This article reports that as many as five colleges or charitable foundations whose endowments have suffered significant investment losses or were unable to access money in their accounts in recent months are considering legal action against their brokers or investment managers, alleging misrepresentation of risk or mismanagement. Jacob H.…

  11. 75 FR 51116 - National Endowment for the Arts;

    Science.gov (United States)

    2010-08-18

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... five meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate): Arts Education (application review): September 14-15, 2010 in Room 714. A portion of...

  12. Interaction control of an UAV endowed with a manipulator

    NARCIS (Netherlands)

    Scholten, Jasper L.J; Fumagalli, Matteo; Stramigioli, Stefano; Carloni, Raffaella

    2013-01-01

    In this paper, we present the design, simulation and experimental validation of a control architecture for an unmanned aerial vehicle endowed with a manipulation system and interacting with a remote environment. The goal of this work is to show that the interaction control allows the ma- nipulator t

  13. For Berkeley's Sports Endowment, a Goal of $1-Billion

    Science.gov (United States)

    Keller, Josh

    2009-01-01

    Most athletics programs, if forced to raise $300-million to renovate a football stadium, would not set an ambitious endowment goal at the same time. The University of California at Berkeley is trying to do both. The university's California Memorial Stadium sits directly over an earthquake fault: it needs a major seismic retrofit that will take…

  14. Aspects of endowment: a query theory of value construction.

    Science.gov (United States)

    Johnson, Eric J; Häubl, Gerald; Keinan, Anat

    2007-05-01

    How do people judge the monetary value of objects? One clue is provided by the typical endowment study (D. Kahneman, J. L. Knetsch, & R. H. Thaler, 1991), in which participants are randomly given either a good, such as a coffee mug, that they may later sell ("sellers") or a choice between the good and amounts of cash ("choosers"). Sellers typically demand at least twice as much as choosers, inconsistent with economic theory. This result is usually explained by an increased weighting of losses, or loss aversion. The authors provide a memory-based account of endowment, suggesting that people construct values by posing a series of queries whose order differs for sellers and choosers. Because of output interference, these queries retrieve different aspects of the object and the medium of exchange, producing different valuations. The authors show that the content and structure of the recalled aspects differ for selling and choosing and that these aspects predict valuations. Merely altering the order in which queries are posed can eliminate the endowment effect, and changing the order of queries can produce endowment-like effects without ownership.

  15. Isolation and culture of neural crest cells from embryonic murine neural tube.

    Science.gov (United States)

    Pfaltzgraff, Elise R; Mundell, Nathan A; Labosky, Patricia A

    2012-06-02

    The embryonic neural crest (NC) is a multipotent progenitor population that originates at the dorsal aspect of the neural tube, undergoes an epithelial to mesenchymal transition (EMT) and migrates throughout the embryo, giving rise to diverse cell types. NC also has the unique ability to influence the differentiation and maturation of target organs. When explanted in vitro, NC progenitors undergo self-renewal, migrate and differentiate into a variety of tissue types including neurons, glia, smooth muscle cells, cartilage and bone. NC multipotency was first described from explants of the avian neural tube. In vitro isolation of NC cells facilitates the study of NC dynamics including proliferation, migration, and multipotency. Further work in the avian and rat systems demonstrated that explanted NC cells retain their NC potential when transplanted back into the embryo. Because these inherent cellular properties are preserved in explanted NC progenitors, the neural tube explant assay provides an attractive option for studying the NC in vitro. To attain a better understanding of the mammalian NC, many methods have been employed to isolate NC populations. NC-derived progenitors can be cultured from post-migratory locations in both the embryo and adult to study the dynamics of post-migratory NC progenitors, however isolation of NC progenitors as they emigrate from the neural tube provides optimal preservation of NC cell potential and migratory properties. Some protocols employ fluorescence activated cell sorting (FACS) to isolate a NC population enriched for particular progenitors. However, when starting with early stage embryos, cell numbers adequate for analyses are difficult to obtain with FACS, complicating the isolation of early NC populations from individual embryos. Here, we describe an approach that does not rely on FACS and results in an approximately 96% pure NC population based on a Wnt1-Cre activated lineage reporter. The method presented here is adapted from

  16. Neural crest cells: from developmental biology to clinical interventions.

    Science.gov (United States)

    Noisa, Parinya; Raivio, Taneli

    2014-09-01

    Neural crest cells are multipotent cells, which are specified in embryonic ectoderm in the border of neural plate and epiderm during early development by interconnection of extrinsic stimuli and intrinsic factors. Neural crest cells are capable of differentiating into various somatic cell types, including melanocytes, craniofacial cartilage and bone, smooth muscle, and peripheral nervous cells, which supports their promise for cell therapy. In this work, we provide a comprehensive review of wide aspects of neural crest cells from their developmental biology to applicability in medical research. We provide a simplified model of neural crest cell development and highlight the key external stimuli and intrinsic regulators that determine the neural crest cell fate. Defects of neural crest cell development leading to several human disorders are also mentioned, with the emphasis of using human induced pluripotent stem cells to model neurocristopathic syndromes. © 2014 Wiley Periodicals, Inc.

  17. Hedgehog signaling is required for cranial neural crest morphogenesis and chondrogenesis at the midline in the zebrafish skull.

    Science.gov (United States)

    Wada, Naoyuki; Javidan, Yashar; Nelson, Sarah; Carney, Thomas J; Kelsh, Robert N; Schilling, Thomas F

    2005-09-01

    Neural crest cells that form the vertebrate head skeleton migrate and interact with surrounding tissues to shape the skull, and defects in these processes underlie many human craniofacial syndromes. Signals at the midline play a crucial role in the development of the anterior neurocranium, which forms the ventral braincase and palate, and here we explore the role of Hedgehog (Hh) signaling in this process. Using sox10:egfp transgenics to follow neural crest cell movements in the living embryo, and vital dye labeling to generate a fate map, we show that distinct populations of neural crest form the two main cartilage elements of the larval anterior neurocranium: the paired trabeculae and the midline ethmoid. By analyzing zebrafish mutants that disrupt sonic hedgehog (shh) expression, we demonstrate that shh is required to specify the movements of progenitors of these elements at the midline, and to induce them to form cartilage. Treatments with cyclopamine, to block Hh signaling at different stages, suggest that although requirements in morphogenesis occur during neural crest migration beneath the brain, requirements in chondrogenesis occur later, as cells form separate trabecular and ethmoid condensations. Cell transplantations indicate that these also reflect different sources of Shh, one from the ventral neural tube that controls trabecular morphogenesis and one from the oral ectoderm that promotes chondrogenesis. Our results suggest a novel role for Shh in the movements of neural crest cells at the midline, as well as in their differentiation into cartilage, and help to explain why both skeletal fusions and palatal clefting are associated with the loss of Hh signaling in holoprosencephalic humans.

  18. Neural crest cell evolution: how and when did a neural crest cell become a neural crest cell.

    Science.gov (United States)

    Muñoz, William A; Trainor, Paul A

    2015-01-01

    As vertebrates evolved from protochordates, they shifted to a more predatory lifestyle, and radiated and adapted to most niches of the planet. This process was largely facilitated by the generation of novel vertebrate head structures, which were derived from neural crest cells (NCC). The neural crest is a unique vertebrate cell population that is frequently termed the "fourth germ layer" because it forms in conjunction with the other germ layers and contributes to a diverse array of cell types and tissues including the craniofacial skeleton, the peripheral nervous system, and pigment cells among many other tissues and cell types. NCC are defined by their origin at the neural plate border, via an epithelial-to-mesenchymal transition (EMT), together with multipotency and polarized patterns of migration. These defining characteristics, which evolved independently in the germ layers of invertebrates, were subsequently co-opted through their gene regulatory networks to form NCC in vertebrates. Moreover, recent data suggest that the ability to undergo an EMT was one of the latter features co-opted by NCC. In this review, we discuss the potential origins of NCC and how they evolved to contribute to nearly all tissues and organs throughout the body, based on paleontological evidence together with an evaluation of the evolution of molecules involved in NCC development and their migratory cell paths.

  19. Evolution of vertebrates as viewed from the crest.

    Science.gov (United States)

    Green, Stephen A; Simoes-Costa, Marcos; Bronner, Marianne E

    2015-04-23

    The origin of vertebrates was accompanied by the advent of a novel cell type: the neural crest. Emerging from the central nervous system, these cells migrate to diverse locations and differentiate into numerous derivatives. By coupling morphological and gene regulatory information from vertebrates and other chordates, we describe how addition of the neural-crest-specification program may have enabled cells at the neural plate border to acquire multipotency and migratory ability. Analysis of the topology of the neural crest gene regulatory network can serve as a useful template for understanding vertebrate evolution, including elaboration of neural crest derivatives.

  20. Evolution of vertebrates: a view from the crest

    Science.gov (United States)

    Bronner, Marianne E.

    2016-01-01

    The origin of vertebrates was accompanied by the advent of a novel cell type: the neural crest. Emerging from the central nervous system, these cells migrate to diverse locations and differentiate into numerous derivatives. By coupling morphological and gene regulatory information from vertebrates and other chordates, we describe how addition of the neural crest specification program may have enabled cells at the neural plate border to acquire multipotency and migratory ability. Analyzing the topology of the neural crest gene regulatory network can serve as a useful template for understanding vertebrate evolution, including elaboration of neural crest derivatives. PMID:25903629

  1. Laboratory Experiments on Low-crested Breakwaters

    DEFF Research Database (Denmark)

    Kramer, Morten; Zanuttigh, B.; van der Meer, J.W.

    2005-01-01

    in a wave channel at small scale, and scale effects regarding wave transmission and reflection were studied in a wave channel at a large scale facility. The paper describes the experiments and associated databank with respect to objectives, test program, set-ups and measurements. Results, guidelines......New unique laboratory experiments on low-crested structures (LCSs) have been performed within the DELOS project. The experiments were carried out in three European laboratories aiming at extending and completing existing available information with respect to a wide range of engineering design...

  2. Taxonomy Icon Data: crested porcupine [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available crested porcupine Hystrix cristata Chordata/Vertebrata/Mammalia/Theria/Eutheria/etc. Hystrix_cristata..._L.png Hystrix_cristata_NL.png Hystrix_cristata_S.png Hystrix_cristata_NS.png http://biosc...iencedbc.jp/taxonomy_icon/icon.cgi?i=Hystrix+cristata&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Hystrix+cristata...&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Hystrix+cristata...&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Hystrix+cristata&t=NS ...

  3. Neural crest: The fourth germ layer

    Directory of Open Access Journals (Sweden)

    K Shyamala

    2015-01-01

    Full Text Available The neural crest cells (NCCs, a transient group of cells that emerges from the dorsal aspect of the neural tube during early vertebrate development has been a fascinating group of cells because of its multipotency, long range migration through embryo and its capacity to generate a prodigious number of differentiated cell types. For these reasons, although derived from the ectoderm, the neural crest (NC has been called the fourth germ layer. The non neural ectoderm, the neural plate and the underlying mesoderm are needed for the induction and formation of NC cells. Once formed, NC cells start migrating as a wave of cells, moving away from the neuroepithelium and quickly splitting into distinct streams. These migrating NCCs home in to different regions and give rise to plethora of tissues. Umpteen number of signaling molecules are essential for formation, epithelial mesenchymal transition, delamination, migration and localization of NCC. Authors believe that a clear understanding of steps and signals involved in NC formation, migration, etc., may help in understanding the pathogenesis behind cancer metastasis and many other diseases. Hence, we have taken this review to discuss the various aspects of the NC cells.

  4. Imidacloprid Exposure Suppresses Neural Crest Cells Generation during Early Chick Embryo Development.

    Science.gov (United States)

    Wang, Chao-Jie; Wang, Guang; Wang, Xiao-Yu; Liu, Meng; Chuai, Manli; Lee, Kenneth Ka Ho; He, Xiao-Song; Lu, Da-Xiang; Yang, Xuesong

    2016-06-15

    Imidacloprid is a neonicotinoid pesticide that is widely used in the control pests found on crops and fleas on pets. However, it is still unclear whether imidacloprid exposure could affect early embryo development-despite some studies having been conducted on the gametes. In this study, we demonstrated that imidacloprid exposure could lead to abnormal craniofacial osteogenesis in the developing chick embryo. Cranial neural crest cells (NCCs) are the progenitor cells of the chick cranial skull. We found that the imidacloprid exposure retards the development of gastrulating chick embryos. HNK-1, PAX7, and Ap-2α immunohistological stainings indicated that cranial NCCs generation was inhibited after imidacloprid exposure. Double immunofluorescent staining (Ap-2α and PHIS3 or PAX7 and c-Caspase3) revealed that imidacloprid exposure inhibited both NCC proliferation and apoptosis. In addition, it inhibited NCCs production by repressing Msx1 and BMP4 expression in the developing neural tube and by altering expression of EMT-related adhesion molecules (Cad6B, E-Cadherin, and N-cadherin) in the developing neural crests. We also determined that imidacloprid exposure suppressed cranial NCCs migration and their ability to differentiate. In sum, we have provided experimental evidence that imidacloprid exposure during embryogenesis disrupts NCCs development, which in turn causes defective cranial bone development.

  5. Endowments at Birth and Parents’ Investments in Children*

    OpenAIRE

    Adhvaryu, Achyuta; Nyshadham, Anant

    2014-01-01

    Do parents invest more in higher quality children, or do they compensate for lower quality by giving more to children with lower endowments? We answer this question in the context of a large-scale iodine supplementation programme in Tanzania. We find that children with higher programme exposure were more likely to receive necessary vaccines and were breastfed for longer. Siblings of treated children were also more likely to be immunised. Fertility behavior and investments at the time of birth...

  6. Discussionon Establishing the System of Rural Society Endowment Insurance

    Institute of Scientific and Technical Information of China (English)

    董超; 厉安健

    2011-01-01

    With the development of rural area's economy and society in China,it is imperative to establish the system of rural society endowment insurance.This paper described the significance and the necessity of establishing this system in details.Meanwhile,it also provided the referencial solution to set up the system of old-age insurance for migrant workers and Chinese farmers whose lands are expropriated by the government.

  7. Prospect Theory: A Study of the Endowment Effect

    Directory of Open Access Journals (Sweden)

    Jurandir Sell Macedo

    2007-01-01

    Full Text Available Behavioral Finance is a recent field of study which contradicts the presupposition supported by Modern Finance that decision makers act rationally. Prospect Theory, developed by Kahneman and Tversky (1979, is presented as an alternative model to the Theory of Expected Utility in relation to the way people decide in face of possibilities of risk. According to Prospect Theory, people define gains and losses based on a given point of reference, which can be established on grounds of a given level of expected gain. This fact leads to the Endowment Effect - a behavioral trend investigated in this study – whereby investors are influenced by a portfolio which they have received as an inheritance or endowment. The reason this occurs is that individuals usually define their expectations of gain according to the future profitability of the portfolio received, and not according to the future profitability of the market. Using an investment simulation, the Endowment Effect was tested among 226 university students taking courses in the subject of capital markets. The results demonstrate that the students were influenced by the different initial portfolios, which were randomly assigned.

  8. Stability of Cubipod Armoured Roundheads in Short Crested Waves

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke; Medina, Josep R.

    2011-01-01

    The paper presents a comparison of the stability of concrete cube armour and Cubipod armour in a breakwater roundhead with slope 1:1.5, exposed to both 2-D (long-crested) and 3-D (short-crested) waves. The model tests were performed at the Hydraulics and Coastal Engineering Laboratory at Aalborg ...

  9. 26 CFR 1.264-2 - Single premium life insurance, endowment, or annuity contracts.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Single premium life insurance, endowment, or..., directly or indirectly, to purchase or to continue in effect a single premium life insurance or endowment... payee of such annuity contract. A contract is considered a single premium life insurance, endowment,...

  10. The limits of endowment effects in great apes (Pan paniscus, Pan troglodytes, Gorilla gorilla, Pongo pygmaeus).

    Science.gov (United States)

    Kanngiesser, Patricia; Santos, Laurie R; Hood, Bruce M; Call, Josep

    2011-11-01

    The endowment effect describes the bias that people often value things that they possess more than things they do not possess. Thus, they are often reluctant to trade items in their possession for items of equivalent value. Some nonhuman primates appear to share this bias with humans, but it remains an open question whether they show endowment effects to the same extent as humans do. We investigated endowment effects in all four great ape species (Pan paniscus, Pan troglodytes, Gorilla gorilla, Pongo pygmaeus) by varying whether apes were endowed with food items (Experiment 1, N = 22) or tools that were instrumental in retrieving food (Experiment 2, N = 23). We first assessed apes' preferences for items of a pair and their willingness to trade items in their possession. We then endowed apes with one item of a pair and offered them to trade for the other item. Apes showed endowment effects for food, but not for tools. In Experiment 3, we endowed bonobos (N = 4) and orangutans (N = 5) with either one or 12 food items. Endowment effects did not differ between species and were not influenced by the number of endowed food items. Our findings suggest that endowment effects in great apes are restricted to immediate food gratification and remain unaffected by the quantity of food rewards. However, endowment effects do not seem to extend to other, nonconsumable possessions even when they are instrumental in retrieving food. In general, apes do not show endowment effects across a range of different commodities as humans typically do.

  11. 45 CFR 1159.7 - Will the Endowment collect information from me for its records?

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Will the Endowment collect information from me for... PRIVACY ACT OF 1974 § 1159.7 Will the Endowment collect information from me for its records? The Endowment shall collect information, to the greatest extent practicable, directly from you when the...

  12. Xenopus reduced folate carrier regulates neural crest development epigenetically.

    Directory of Open Access Journals (Sweden)

    Jiejing Li

    Full Text Available Folic acid deficiency during pregnancy causes birth neurocristopathic malformations resulting from aberrant development of neural crest cells. The Reduced folate carrier (RFC is a membrane-bound receptor for facilitating transfer of reduced folate into the cells. RFC knockout mice are embryonic lethal and develop multiple malformations, including neurocristopathies. Here we show that XRFC is specifically expressed in neural crest tissues in Xenopus embryos and knockdown of XRFC by specific morpholino results in severe neurocristopathies. Inhibition of RFC blocked the expression of a series of neural crest marker genes while overexpression of RFC or injection of 5-methyltetrahydrofolate expanded the neural crest territories. In animal cap assays, knockdown of RFC dramatically reduced the mono- and trimethyl-Histone3-K4 levels and co-injection of the lysine methyltransferase hMLL1 largely rescued the XRFC morpholino phenotype. Our data revealed that the RFC mediated folate metabolic pathway likely potentiates neural crest gene expression through epigenetic modifications.

  13. Are neural crest stem cells the missing link between hematopoietic and neurogenic niches?

    Science.gov (United States)

    Coste, Cécile; Neirinckx, Virginie; Gothot, André; Wislet, Sabine; Rogister, Bernard

    2015-01-01

    Hematopoietic niches are defined as cellular and molecular microenvironments that regulate hematopoietic stem cell (HSC) function together with stem cell autonomous mechanisms. Many different cell types have been characterized as contributors to the formation of HSC niches, such as osteoblasts, endothelial cells, Schwann cells, and mesenchymal progenitors. These mesenchymal progenitors have themselves been classified as CXC chemokine ligand (CXCL) 12-abundant reticular (CAR) cells, stem cell factor expressing cells, or nestin-positive mesenchymal stem cells (MSCs), which have been recently identified as neural crest-derived cells (NCSCs). Together, these cells are spatially associated with HSCs and believed to provide appropriate microenvironments for HSC self-renewal, differentiation, mobilization and hibernation both by cell-cell contact and soluble factors. Interestingly, it appears that regulatory pathways governing the hematopoietic niche homeostasis are operating in the neurogenic niche as well. Therefore, this review paper aims to compare both the regulation of hematopoietic and neurogenic niches, in order to highlight the role of NCSCs and nervous system components in the development and the regulation of the hematopoietic system.

  14. Are neural crest stem cells the missing link between hematopoietic and neurogenic niches?

    Directory of Open Access Journals (Sweden)

    Cécile eCoste

    2015-06-01

    Full Text Available Hematopoietic niches are defined as cellular and molecular microenvironments that regulate hematopoietic stem cell (HSC function together with stem cell autonomous mechanisms. Many different cell types have been characterized as contributors to the formation of HSC niches, such as osteoblasts, endothelial cells, Schwann cells, and mesenchymal progenitors. These mesenchymal progenitors have themselves been classified as CXC chemokine ligand (CXCL12-abundant reticular (CAR cells, stem cell factor expressing cells, or nestin-positive mesenchymal stem cells (MSCs, which have been recently identified as neural crest-derived cells (NCSCs. Together, these cells are spatially associated with HSCs and believed to provide appropriate microenvironments for HSC self-renewal, differentiation, mobilization and hibernation both by cell-to-cell contact and soluble factors. Interestingly, it appears that regulatory pathways governing the hematopoietic niche homeostasis are operating in the neurogenic niche as well. Therefore, this review paper aims to compare both the regulation of hematopoietic and neurogenic niches, in order to highlight the role of NCSCs and nervous system components in the development and the regulation of the hematopoietic system.

  15. Reiterative AP2a activity controls sequential steps in the neural crest gene regulatory network.

    Science.gov (United States)

    de Crozé, Noémie; Maczkowiak, Frédérique; Monsoro-Burq, Anne H

    2011-01-04

    The neural crest (NC) emerges from combinatorial inductive events occurring within its progenitor domain, the neural border (NB). Several transcription factors act early at the NB, but the initiating molecular events remain elusive. Recent data from basal vertebrates suggest that ap2 might have been critical for NC emergence; however, the role of AP2 factors at the NB remains unclear. We show here that AP2a initiates NB patterning and is sufficient to elicit a NB-like pattern in neuralized ectoderm. In contrast, the other early regulators do not participate in ap2a initiation at the NB, but cooperate to further establish a robust NB pattern. The NC regulatory network uses a multistep cascade of secreted inducers and transcription factors, first at the NB and then within the NC progenitors. Here we report that AP2a acts at two distinct steps of this cascade. As the earliest known NB specifier, AP2a mediates Wnt signals to initiate the NB and activate pax3; as a NC specifier, AP2a regulates further NC development independent of and downstream of NB patterning. Our findings reconcile conflicting observations from various vertebrate organisms. AP2a provides a paradigm for the reiterated use of multifunctional molecules, thereby facilitating emergence of the NC in vertebrates.

  16. Cranial neural crest-derived mesenchymal proliferation is regulated by Msx1-mediated p19(INK4d) expression during odontogenesis.

    Science.gov (United States)

    Han, Jun; Ito, Yoshihiro; Yeo, Jae Yong; Sucov, Henry M; Maas, Richard; Chai, Yang

    2003-09-01

    Neural crest cells are multipotential progenitors that contribute to various cell and tissue types during embryogenesis. Here, we have investigated the molecular and cellular mechanism by which the fate of neural crest cell is regulated during tooth development. Using a two- component genetic system for indelibly marking the progeny of neural crest cells, we provide in vivo evidence of a deficiency of CNC-derived dental mesenchyme in Msx1 null mutant mouse embryos. The deficiency of the CNC results from an elevated CDK inhibitor p19(INK4d) activity and the disruption of cell proliferation. Interestingly, in the absence of Msx1, the CNC-derived dental mesenchyme misdifferentiates and possesses properties consistent with a neuronal fate, possibly through a default mechanism. Attenuation of p19(INK4d) in Msx1 null mutant mandibular explants restores mitotic activity in the dental mesenchyme, demonstrating the functional significance of Msx1-mediated p19(INK4d) expression in regulating CNC cell proliferation during odontogenesis. Collectively, our results demonstrate that homeobox gene Msx1 regulates the fate of CNC cells by controlling the progression of the cell cycle. Genetic mutation of Msx1 may alternatively instruct the fate of these progenitor cells during craniofacial development.

  17. Trunk neural crest cells: formation, migration and beyond.

    Science.gov (United States)

    Vega-Lopez, Guillermo A; Cerrizuela, Santiago; Aybar, Manuel J

    2017-01-01

    Neural crest cells (NCCs) are a multipotent, migratory cell population that generates an astonishingly diverse array of cell types during vertebrate development. The trunk neural crest has long been considered of particular significance. First, it has been held that the trunk neural crest has a morphogenetic role, acting to coordinate the development of the peripheral nervous system, secretory cells of the endocrine system and pigment cells of the skin. Second, the trunk neural crest additionally has skeletal potential. However, it has been demonstrated that a key role of the trunk neural crest streams is to organize the innervation of the intestine. Although trunk NCCs have a limited capacity for self-renewal, sometimes they become neural-crest-derived tumor cells and reveal the fact that that NCCs and tumor cells share the same molecular machinery. In this review we describe the routes taken by trunk NCCs and consider the signals and cues that pattern these trajectories. We also discuss recent advances in the characterization of the properties of trunk NCCs for various model organisms in order to highlight common themes. Finally, looking to the future, we discuss the need to translate the wealth of data from animal studies to the clinical area in order to develop treatments for neural crest-related human diseases.

  18. Cardiac neural crest contributes to cardiomyogenesis in zebrafish.

    Science.gov (United States)

    Sato, Mariko; Yost, H Joseph

    2003-05-01

    In birds and mammals, cardiac neural crest is essential for heart development and contributes to conotruncal cushion formation and outflow tract septation. The zebrafish prototypical heart lacks outflow tract septation, raising the question of whether cardiac neural crest exists in zebrafish. Here, results from three distinct lineage-labeling approaches identify zebrafish cardiac neural crest cells and indicate that these cells have the ability to generate MF20-positive muscle cells in the myocardium of the major chambers during development. Fate-mapping demonstrates that cardiac neural crest cells originate both from neural tube regions analogous to those found in birds, as well as from a novel region rostral to the otic vesicle. In contrast to other vertebrates, cardiac neural crest invades the myocardium in all segments of the heart, including outflow tract, atrium, atrioventricular junction, and ventricle in zebrafish. Three distinct groups of premigratory neural crest along the rostrocaudal axis have different propensities to contribute to different segments in the heart and are correspondingly marked by unique combinations of gene expression patterns. Zebrafish will serve as a model for understanding interactions between cardiac neural crest and cardiovascular development.

  19. Experimental evidence for mutual inter- and intrasexual selection favouring a crested auklet ornament.

    Science.gov (United States)

    Jones; Hunter

    1999-03-01

    During the breeding season, female and male crested auklets Aethia cristatella (Alcidae), display similar conspicuous crest ornaments composed of elongated forward-curving feathers on their foreheads. Based on quantifications of brief agonistic interactions at a large breeding colony, we found that crest length was strongly correlated with dominance within both sexes. Across the full range of crest length, individuals with longer crests were dominant over shorter-crested individuals in agonistic interactions involving same-sex adults. Within subadults (2-year-olds of unknown sex), there was a similar trend towards longer-crested individuals being dominant. In agonistic interactions involving individuals of different sex and age, adult males were dominant over adult females and adults were dominant over subadults, regardless of crest length. In an experiment in which we manipulated crest length using life-size realistic models, male auklets that responded were less aggressive to male models with longer crests than to models with normal or shorter crests, confirming that crest length by itself signals dominance status. In a related experiment in which we controlled intrasexual competition, both males and females responded to opposite-sex models with more frequent sexual displays when the models had long crests compared with those having short crests, suggesting that crested auklets also have mating preferences that favour long crest ornaments. Taken together, these results support the idea that the crest ornament is favoured by both intra- and intersexual selection. Copyright 1999 The Association for the Study of Animal Behaviour.

  20. Maternal Fat Feeding Augments Offspring Nephron Endowment in Mice

    Science.gov (United States)

    Hokke, Stacey; Puelles, Victor G.; Armitage, James A.; Fong, Karen; Bertram, John F.; Cullen-McEwen, Luise A.

    2016-01-01

    Increasing consumption of a high fat 'Western' diet has led to a growing number of pregnancies complicated by maternal obesity. Maternal overnutrition and obesity have health implications for offspring, yet little is known about their effects on offspring kidney development and renal function. Female C57Bl6 mice were fed a high fat diet (HFD, 21% fat) or matched normal fat diet (NFD, 6% fat) for 6 weeks prior to pregnancy and throughout gestation and lactation. HFD dams were overweight and glucose intolerant prior to mating but not in late gestation. Offspring of NFD and HFD dams had similar body weights at embryonic day (E)15.5, E18.5 and at postnatal day (PN)21. HFD offspring had normal ureteric tree development and nephron number at E15.5. However, using unbiased stereology, kidneys of HFD offspring were found to have 20–25% more nephrons than offspring of NFD dams at E18.5 and PN21. Offspring of HFD dams with body weight and glucose profiles similar to NFD dams prior to pregnancy also had an elevated nephron endowment. At 9 months of age, adult offspring of HFD dams displayed mild fasting hyperglycaemia but similar body weights to NFD offspring. Renal function and morphology, measured by transcutaneous clearance of FITC-sinistrin and stereology respectively, were normal. This study demonstrates that maternal fat feeding augments offspring nephron endowment with no long-term consequences for offspring renal health. Future studies assessing the effects of a chronic stressor on adult mice with augmented nephron number are warranted, as are studies investigating the molecular mechanisms that result in high nephron endowment. PMID:27547968

  1. An FGF3-BMP Signaling Axis Regulates Caudal Neural Tube Closure, Neural Crest Specification and Anterior-Posterior Axis Extension.

    Directory of Open Access Journals (Sweden)

    Matthew J Anderson

    2016-05-01

    Full Text Available During vertebrate axis extension, adjacent tissue layers undergo profound morphological changes: within the neuroepithelium, neural tube closure and neural crest formation are occurring, while within the paraxial mesoderm somites are segmenting from the presomitic mesoderm (PSM. Little is known about the signals between these tissues that regulate their coordinated morphogenesis. Here, we analyze the posterior axis truncation of mouse Fgf3 null homozygotes and demonstrate that the earliest role of PSM-derived FGF3 is to regulate BMP signals in the adjacent neuroepithelium. FGF3 loss causes elevated BMP signals leading to increased neuroepithelium proliferation, delay in neural tube closure and premature neural crest specification. We demonstrate that elevated BMP4 depletes PSM progenitors in vitro, phenocopying the Fgf3 mutant, suggesting that excessive BMP signals cause the Fgf3 axis defect. To test this in vivo we increased BMP signaling in Fgf3 mutants by removing one copy of Noggin, which encodes a BMP antagonist. In such mutants, all parameters of the Fgf3 phenotype were exacerbated: neural tube closure delay, premature neural crest specification, and premature axis termination. Conversely, genetically decreasing BMP signaling in Fgf3 mutants, via loss of BMP receptor activity, alleviates morphological defects. Aberrant apoptosis is observed in the Fgf3 mutant tailbud. However, we demonstrate that cell death does not cause the Fgf3 phenotype: blocking apoptosis via deletion of pro-apoptotic genes surprisingly increases all Fgf3 defects including causing spina bifida. We demonstrate that this counterintuitive consequence of blocking apoptosis is caused by the increased survival of BMP-producing cells in the neuroepithelium. Thus, we show that FGF3 in the caudal vertebrate embryo regulates BMP signaling in the neuroepithelium, which in turn regulates neural tube closure, neural crest specification and axis termination. Uncovering this FGF3

  2. An FGF3-BMP Signaling Axis Regulates Caudal Neural Tube Closure, Neural Crest Specification and Anterior-Posterior Axis Extension.

    Science.gov (United States)

    Anderson, Matthew J; Schimmang, Thomas; Lewandoski, Mark

    2016-05-01

    During vertebrate axis extension, adjacent tissue layers undergo profound morphological changes: within the neuroepithelium, neural tube closure and neural crest formation are occurring, while within the paraxial mesoderm somites are segmenting from the presomitic mesoderm (PSM). Little is known about the signals between these tissues that regulate their coordinated morphogenesis. Here, we analyze the posterior axis truncation of mouse Fgf3 null homozygotes and demonstrate that the earliest role of PSM-derived FGF3 is to regulate BMP signals in the adjacent neuroepithelium. FGF3 loss causes elevated BMP signals leading to increased neuroepithelium proliferation, delay in neural tube closure and premature neural crest specification. We demonstrate that elevated BMP4 depletes PSM progenitors in vitro, phenocopying the Fgf3 mutant, suggesting that excessive BMP signals cause the Fgf3 axis defect. To test this in vivo we increased BMP signaling in Fgf3 mutants by removing one copy of Noggin, which encodes a BMP antagonist. In such mutants, all parameters of the Fgf3 phenotype were exacerbated: neural tube closure delay, premature neural crest specification, and premature axis termination. Conversely, genetically decreasing BMP signaling in Fgf3 mutants, via loss of BMP receptor activity, alleviates morphological defects. Aberrant apoptosis is observed in the Fgf3 mutant tailbud. However, we demonstrate that cell death does not cause the Fgf3 phenotype: blocking apoptosis via deletion of pro-apoptotic genes surprisingly increases all Fgf3 defects including causing spina bifida. We demonstrate that this counterintuitive consequence of blocking apoptosis is caused by the increased survival of BMP-producing cells in the neuroepithelium. Thus, we show that FGF3 in the caudal vertebrate embryo regulates BMP signaling in the neuroepithelium, which in turn regulates neural tube closure, neural crest specification and axis termination. Uncovering this FGF3-BMP signaling axis is

  3. Activities of Endowment Funds for the Period of Destabilization of the Economy

    Directory of Open Access Journals (Sweden)

    Alan Pavlovich Abaev

    2016-10-01

    Full Text Available Endowment fund is gaining its importance as a source of financing higher education institution, and, therefore, the research of endowments’ activities is an urgent task. The current state of the economy in Russia is most often characterized as recessionary. The article sets the task to assess the conditions of endowment funds in times of crisis, under existing sanctions, lower oil quotations and other factors, as well as to analyze the profitability of endowment funds in this period. The study showed that the slowdown in the economy was reflected in the activities of endowment funds. Yield investment strategies significantly decreased in comparison with previous periods. The evaluation of the impact of various economic and political factors on the activities of endowment funds reveals their weaknesses and justifies the need for new approaches in the work of endowment funds. According to the author, the main problem is the lack of opportunities to invest in high-yield financial instruments (investments in futures, options, etc.. Therefore, in the years of economic instability it is more difficult for management companies to balance the profitability of the investment portfolios of endowment funds. According to a study of thirty endowment funds, yield for 2014 was 4.68 %, which did not exceed inflation. The financial turmoil in the world is reflected in the activities of endowment funds. Thereby giving rise to the need for new approaches in the work of endowment funds would enable them to overcome the existing problems and be more resilient in the future.

  4. Crested wheatgrass control and monitoring Benton Lake Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Crested wheatgrass (CWG) was planted on Benton Lake NWR at least 30 years ago, presumably to stabilize the soil where it had been disturbed in the process of...

  5. Cryoglobulinemic vasculitis in a patient with CREST syndrome.

    Science.gov (United States)

    Hurst, Rebecca L; Berianu, Florentina; Ginsburg, William W; Klein, Christopher J; Englestad, Janean K; Kennelly, Kathleen D

    2014-10-01

    Cryoglobulinemic vasculitis is a rare entity. Although it has been reported in diffuse systemic sclerosis, it has not been reported in calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly and telangiectasia (CREST) syndrome. We report a patient with cryoglobulinemic vasculitis with CREST syndrome who did not have typical clinical features of vasculitis. This 58-year-old woman presented with mild generalized weakness and a diagnosis of CREST syndrome, which included Raynaud's syndrome, dysphagia and telangiectasias. She was positive for serum cryoglobulins, which led to a sural nerve biopsy. The biopsy results were consistent with cryoglobulinemic vasculitis. Cryoglobulinemic vasculitis has not been previously reported in CREST syndrome to our knowledge. Additionally, the patient also had limited clinical symptoms. Our patient displays the importance of checking for cryoglobulins and obtaining a nerve biopsy when the serum is positive. Both of these diagnostic tests were integral for directing appropriate treatment for this patient.

  6. Why I Lost My Secretary: The Effect of Endowment Shocks on University Operations. NBER Working Paper No. 15861

    Science.gov (United States)

    Brown, Jeffrey; Dimmock, Stephen G.; Kang, Jun-Koo; Weisbenner, Scott

    2010-01-01

    Over the past two decades, endowments have become an increasingly important component of the typical university's resource base. We examine how U.S. doctoral institutions' endowment payout policies and spending decisions are affected by financial market shocks to endowments. While most endowments have formal payout policies intended to smooth…

  7. Flow structure in front of the broad-crested weir

    Directory of Open Access Journals (Sweden)

    Zachoval Zbyněk

    2015-01-01

    Full Text Available The paper deals with research focused on description of flow structure in front of broad-crested weir. Based on experimental measurement, the flow structure in front of the weir (the recirculation zone of flow and tornado vortices and flow structure on the weir crest has been described. The determined flow character has been simulated using numerical model and based on comparing results the suitable model of turbulence has been recommended.

  8. CREST syndrome and periodontal surgery: a case report.

    Science.gov (United States)

    Stanford, T W; Peterson, J; Machen, R L

    1999-05-01

    CREST syndrome is a slowly progressive form of systemic scleroderma. It is characterized by calcinosis cutis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia. There are limited reports of dental treatment for patients with this syndrome, and no reports of periodontal surgical procedures. This paper presents a case report of periodontal surgical treatment in a 38-year-old female patient with CREST syndrome, and a discussion of the clinical manifestations of the syndrome as they relate to dental treatment.

  9. A dynamic code of dorsal neural tube genes regulates the segregation between neurogenic and melanogenic neural crest cells.

    Science.gov (United States)

    Nitzan, Erez; Krispin, Shlomo; Pfaltzgraff, Elise R; Klar, Avihu; Labosky, Patricia A; Kalcheim, Chaya

    2013-06-01

    Understanding when and how multipotent progenitors segregate into diverse fates is a key question during embryonic development. The neural crest (NC) is an exemplary model system with which to investigate the dynamics of progenitor cell specification, as it generates a multitude of derivatives. Based on 'in ovo' lineage analysis, we previously suggested an early fate restriction of premigratory trunk NC to generate neural versus melanogenic fates, yet the timing of fate segregation and the underlying mechanisms remained unknown. Analysis of progenitors expressing a Foxd3 reporter reveals that prospective melanoblasts downregulate Foxd3 and have already segregated from neural lineages before emigration. When this downregulation is prevented, late-emigrating avian precursors fail to upregulate the melanogenic markers Mitf and MC/1 and the guidance receptor Ednrb2, generating instead glial cells that express P0 and Fabp. In this context, Foxd3 lies downstream of Snail2 and Sox9, constituting a minimal network upstream of Mitf and Ednrb2 to link melanogenic specification with migration. Consistent with the gain-of-function data in avians, loss of Foxd3 function in mouse NC results in ectopic melanogenesis in the dorsal tube and sensory ganglia. Altogether, Foxd3 is part of a dynamically expressed gene network that is necessary and sufficient to regulate fate decisions in premigratory NC. Their timely downregulation in the dorsal neural tube is thus necessary for the switch between neural and melanocytic phases of NC development.

  10. Analysis on Endowment of Empty Nesters in Tulu Village of Hunchun City in Jilin Province

    Institute of Scientific and Technical Information of China (English)

    Yuji; JIN; Meina; JIANG

    2015-01-01

    with expansion of rural empty nesters,endowment of empty nesters has become a hot spot of the society. By means of questionnaire survey and interview,this paper analyzed basic situations of empty nesters in Tulu Village of Hunchun City in Jilin Province,including economic level,physical health,life care,and spirit situations. Next,it discussed major problems in endowment problem of empty nesters,including limited economic support,unoptimistic physical health,low ability of life care,and feeling of loneliness. Finally,it came up with pertinent recommendations on the basis of the analysis,including strengthening family endowment ability and improving socialized endowment service,strengthening practical living ability,improving life care ability with family endowment as primary and community endowment as auxiliary part,and expanding amusement and recreation ways of empty nesters.

  11. Comparing Effects of Four Toothpaste Types (Nasim, Crest 7, Crest Sensitivity and Daroghar3) on Rate of Enamel Abrasion

    OpenAIRE

    2016-01-01

    Introduction: Toothpaste should have the most plaque removal efficacy with the least abrasiveness. The aim of this study was to evaluate enamel abrasion induced by four toothpaste types. Methods: In this in vitro experimental study, 24 dental samples were divided into four groups of six. The initial surface roughness was measured with the roughness measuring device. Regarding abrasion test with Daroghar3, Nasim, Crest7 and Crest sensitivity toothpastes, samples were located in V8cross brus...

  12. No endowment effect when people transact secondhand goods over the Internet

    OpenAIRE

    Sergio Da Silva; Raul Matsushita; Eliza Silveira

    2015-01-01

    We set up a field experiment of the endowment effect by considering thrift shops in Facebook chat rooms and college chat rooms dedicated to secondhand goods transactions. Owners of goods held for use are generally expected to show the endowment effect, but here we show these very owners (most of them females) switch to a trader-like behavior when conducting transactions in the thrift shops and, as a result, the endowment effect vanishes.

  13. Constructing Index System for Evaluating Work Level in Rural Endowment Insurance

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhigang; WANG Yalin

    2008-01-01

    This paper used fuzzy math principles,analyzed different aspects of the work of the current rural endowment insurance and formed the indices to assess the work level of the rural endowment insurance. After selecting the indices of the work level seientificly, constructed the index system to evaluate the work level of the rural endowment insurance and the index system was expressed in the form of math equation.In this way,an objective standard used to evaluate the work level of rural endowment insurance was establised.

  14. The neural correlates of endowment effect without economic transaction.

    Science.gov (United States)

    Votinov, Mikhail; Mima, Tatsuya; Aso, Toshihiko; Abe, Mitsunari; Sawamoto, Nobukatsu; Shinozaki, Jun; Fukuyama, Hidenao

    2010-09-01

    People always concern about what they have and what they might lose even it is just imaginary property. According to Prospect Theory, the losses might be weighted by subjects higher than gain, which would cause the disparity between the willingness to accept (WTA) and willingness to pay (WTP) compensation in economic valuation. Using functional MRI, we investigated neural correlates of this inconsistent value estimation, known as the endowment effect, during a simple pricing task without economic transaction. Brain activation associated with this price discrepancy was observed in the right inferior frontal gyrus (IFG), where voxel-based morphometry of MRI revealed the positive correlation between gray matter concentration and WTA/WTP ratio. These findings suggest the functional relevance of IFG in WTA/WTP discrepancy for pricing without any actual gain and loss, where an integration of loss aversion-related signals from insula and expected value signals may occur.

  15. Proceedings of the ENDOW Workshop 'Offshore Wakes: measurements and Modelling'

    DEFF Research Database (Denmark)

    2002-01-01

    The papers presented in these Proceedings are the result of a workshop held at Risø National Laboratory on March 7 and 8 2002 entitled 'Offshore Wakes: Measurements and Modelling'. The Workshop was arranged to showcase results of the European Communitysupported project 'Efficient Development...... of Offshore Windfarms (ENDOW)' and featured a series of eight presentations discussing modelling of wakes and boundary layers, existing and new measurements from offshore wind farms and how these will be linked ina new design tool and applied at planned offshore wind farms. In addition seven invited...... presentations covered a range of relevant topics from analytical approaches to fatigue and extreme loads in wind turbine clusters, current wake modelling in WAsP,optimising power production at Arklow Bank, Particle Image Velocimetry study of a wind turbine wake in a yaw, offshore wind measurements...

  16. Endocrine and other physiologic modulators of perinatal cardiomyocyte endowment

    Science.gov (United States)

    Jonker, S S; Louey, S

    2015-01-01

    Immature contractile cardiomyocytes proliferate to rapidly increase cell number, establishing cardiomyocyte endowment in the perinatal period. Developmental changes in cellular maturation, size and attrition further contribute to cardiac anatomy. These physiological processes occur concomitant with a changing hormonal environment as the fetus prepares itself for the transition to extrauterine life. There are complex interactions between endocrine, hemodynamic and nutritional regulators of cardiac development. Birth has been long assumed to be the trigger for major differences between the fetal and postnatal cardiomyocyte growth patterns, but investigations in normally growing sheep and rodents suggest this may not be entirely true; in sheep, these differences are initiated before birth, while in rodents they occur after birth. The aim of this review is to draw together our understanding of the temporal regulation of these signals and cardiomyocyte responses relative to birth. Further, we consider how these dynamics are altered in stressed and suboptimal intrauterine environments. PMID:26432905

  17. Role of DNMT3B in the regulation of early neural and neural crest specifiers.

    Science.gov (United States)

    Martins-Taylor, Kristen; Schroeder, Diane I; LaSalle, Janine M; Lalande, Marc; Xu, Ren-He

    2012-01-01

    The de novo DNA methyltransferase DNMT3B functions in establishing DNA methylation patterns during development. DNMT3B missense mutations cause immunodeficiency, centromere instability and facial anomalies (ICF) syndrome. The restriction of Dnmt3b expression to neural progenitor cells, as well as the mild cognitive defects observed in ICF patients, suggests that DNMT3B may play an important role in early neurogenesis. We performed RNAi knockdown of DNMT3B in human embryonic stem cells (hESCs) in order to investigate the mechanistic contribution of DNMT3B to DNA methylation and early neuronal differentiation. While DNMT3B was not required for early neuroepithelium specification, DNMT3B deficient neuroepithelium exhibited accelerated maturation with earlier expression, relative to normal hESCs, of mature neuronal markers (such as NEUROD1) and of early neuronal regional specifiers (such as those for the neural crest). Genome-wide analyses of DNA methylation by MethylC-seq identified novel regions of hypomethylation in the DNMT3B knockdowns along the X chromosome as well as pericentromeric regions, rather than changes to promoters of specific dysregulated genes. We observed a loss of H3K27me3 and the polycomb complex protein EZH2 at the promoters of early neural and neural crest specifier genes during differentiation of DNMT3B knockdown but not normal hESCs. Our results indicate that DNMT3B mediates large-scale methylation patterns in hESCs and that DNMT3B deficiency in the cells alters the timing of their neuronal differentiation and maturation.

  18. From progenitor to afterlife

    CERN Document Server

    Chevalier, R A

    2006-01-01

    The sequence of massive star supernova types IIP (plateau light curve), IIL (linear light curve), IIb, IIn (narrow line), Ib, and Ic roughly represents a sequence of increasing mass loss during the stellar evolution. The mass loss affects the velocity distribution of the ejecta composition; in particular, only the IIP's typically end up with H moving at low velocity. Radio and X-ray observations of extragalactic supernovae show varying mass loss properties that are in line with expectations for the progenitor stars. For young supernova remnants, pulsar wind nebulae and circumstellar interaction provide probes of the inner ejecta and higher velocity ejecta, respectively. Among the young remnants, there is evidence for supernovae over a range of types, including those that exploded with much of the H envelope present (Crab Nebula, 3C 58, 0540--69) and those that exploded after having lost most of their H envelope (Cas A, G292.0+1.8).

  19. CREST--classification resources for environmental sequence tags.

    Directory of Open Access Journals (Sweden)

    Anders Lanzén

    Full Text Available Sequencing of taxonomic or phylogenetic markers is becoming a fast and efficient method for studying environmental microbial communities. This has resulted in a steadily growing collection of marker sequences, most notably of the small-subunit (SSU ribosomal RNA gene, and an increased understanding of microbial phylogeny, diversity and community composition patterns. However, to utilize these large datasets together with new sequencing technologies, a reliable and flexible system for taxonomic classification is critical. We developed CREST (Classification Resources for Environmental Sequence Tags, a set of resources and tools for generating and utilizing custom taxonomies and reference datasets for classification of environmental sequences. CREST uses an alignment-based classification method with the lowest common ancestor algorithm. It also uses explicit rank similarity criteria to reduce false positives and identify novel taxa. We implemented this method in a web server, a command line tool and the graphical user interfaced program MEGAN. Further, we provide the SSU rRNA reference database and taxonomy SilvaMod, derived from the publicly available SILVA SSURef, for classification of sequences from bacteria, archaea and eukaryotes. Using cross-validation and environmental datasets, we compared the performance of CREST and SilvaMod to the RDP Classifier. We also utilized Greengenes as a reference database, both with CREST and the RDP Classifier. These analyses indicate that CREST performs better than alignment-free methods with higher recall rate (sensitivity as well as precision, and with the ability to accurately identify most sequences from novel taxa. Classification using SilvaMod performed better than with Greengenes, particularly when applied to environmental sequences. CREST is freely available under a GNU General Public License (v3 from http://apps.cbu.uib.no/crest and http://lcaclassifier.googlecode.com.

  20. Progenitors of type Ia supernovae

    CERN Document Server

    Maeda, Keiichi

    2016-01-01

    Natures of progenitors of type Ia Supernovae (SNe Ia) have not yet been clarified. There has been long and intensive discussion on whether the so-called single degenerate (SD) scenario or the double degenerate (DD) scenario, or anything else, could explain a major population of SNe Ia, but the conclusion has not yet been reached. With rapidly increasing observational data and new theoretical ideas, the field of studying the SN Ia progenitors has been quickly developing, and various new insights have been obtained in recent years. This article aims at providing a summary of the current situation regarding the SN Ia progenitors, both in theory and observations. It seems difficult to explain the emerging diversity seen in observations of SNe Ia by a single population, and we emphasize that it is important to clarify links between different progenitor scenarios and different sub-classes of SNe Ia.

  1. Through the Lens of Maslow's Hierarchy: Understanding Endowment Accumulation at Private Colleges and Universities

    Science.gov (United States)

    Flabiano, Heather Lynn

    2013-01-01

    Colleges and universities have been questioned regarding their use of endowments, with critics maintaining that these assets have significance beyond the financial benefits they provide and suggesting that institutions hoard endowment to attain unnecessary intangibles such as prestige. A few scholars have attempted to study the purposes of…

  2. Through the Lens of Maslow's Hierarchy: Understanding Endowment Accumulation at Private Colleges and Universities

    Science.gov (United States)

    Flabiano, Heather Lynn

    2013-01-01

    Colleges and universities have been questioned regarding their use of endowments, with critics maintaining that these assets have significance beyond the financial benefits they provide and suggesting that institutions hoard endowment to attain unnecessary intangibles such as prestige. A few scholars have attempted to study the purposes of…

  3. The Boeing Company gives $50,000 to Student Design Team Endowment

    OpenAIRE

    Nystrom, Lynn A.

    2007-01-01

    Last April, Virginia Tech's Student Engineers' Council (SEC) announced the creation of an endowment to benefit student design teams at the university. With the beginning of the fall semester, The Boeing Company increased the size of this endowment with a gift of $50,000 from its Global Corporate Citizenship (GCC) disaster relief team budget.

  4. 76 FR 62094 - National Endowment for the Arts; National Council on the Arts 174th Meeting

    Science.gov (United States)

    2011-10-06

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; National Council on the Arts 174th Meeting... hereby given that a meeting of the National Council on the Arts will be held on October 28, 2011 in Room..., please contact the Office of AccessAbility, National Endowment for the Arts, 1100 Pennsylvania Avenue,...

  5. 36 CFR 1281.14 - What type of endowment is required for a Presidential library?

    Science.gov (United States)

    2010-07-01

    ... required for a Presidential library? 1281.14 Section 1281.14 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.14 What type of endowment is required for a Presidential library? (a) Endowment requirement—new libraries. The foundation or...

  6. Debt, investment and endowment accumulation: the case of not-for-profit hospitals.

    Science.gov (United States)

    Gentry, William M

    2002-09-01

    Not-for-profit hospitals benefit from special tax rules that allow state authorities to issue tax-exempt bonds on their behalf, which may affect their investment and financing choices. Hospitals may respond by increasing their investment in physical assets; however, they may also engage in tax arbitrage by using the tax-exempt debt while maintaining endowment assets. The paper combines data from tax (information) returns and the annual survey of hospitals by the American Hospital Association for 1993-1996. Overall, the results are consistent with substantial tax planning by not-for-profit hospitals. Of the US$ 55.9 billion in tax-exempt liabilities of hospitals in 1996, as much as US$ 32.6 billion could have been eliminated if hospitals spent their endowments instead of borrowing. Furthermore, controlling for hospital size (in terms of revenues and operating assets), endowment assets are associated with a higher ratio of tax-exempt (or total) debt to operating assets. In contrast, endowment assets are not related to taxable debt suggesting that the effects of the endowment on borrowing are motivated by tax incentives. Investment and endowment accumulation regressions suggest that increases in debt increase both physical investment and endowment accumulation but these effects are concentrated among cash-rich hospitals for which the effects on endowment accumulation effects are larger than the effects on physical investment.

  7. Surface Roughness Effects on Discharge Coefficient of Broad Crested Weir

    Directory of Open Access Journals (Sweden)

    Shaker A. Jalil

    2014-06-01

    Full Text Available The aim of this study is to investigate the effects of surface roughness sizes on the discharge coefficient for a broad crested weirs. For this purpose, three models having different lengths of broad crested weirs were tested in a horizontal flume. In each model, the surface was roughed four times. Experimental results of all models showed that the logical negative effect of roughness increased on the discharge (Q for different values of length. The performance of broad crested weir improved with decrease ratio of roughness to the weir height (Ks/P and with the increase of the total Head to the Length (H/L. An empirical equation was obtained to estimate the variation of discharge coefficient Cd in terms total head to length ratio, with total head to roughness ratio.

  8. Observations of highly localized oscillons with multiple crests and troughs

    CERN Document Server

    LI, Xiaochen; Liao, Shijun

    2014-01-01

    Stable, highly localized Faraday's resonant standing waves with multiple crests and troughs were observed in the alcoholic solution partly filled in a Hele-Shaw cell vertically oscillated with a single frequency. Two types of oscillons were observed. The influence of the experimental parameters (such as the concentration of alcoholic solution, the water depth, the frequency and acceleration amplitude of oscillation) on these oscillons were investigated in details. In the same experimental parameters, all of these oscillons have the almost same wave height but rather irregular crest-to-crest distances. Our experiments highly suggest that the complicated oscillons can be regarded as combination of the two elementary oscillons discovered by Rajchenbach et al. (Physical Review Letters, 107, 2011).

  9. Neural crest patterning and the evolution of the jaw.

    Science.gov (United States)

    Kimmel, C B; Miller, C T; Keynes, R J

    2001-01-01

    Here we present ideas connecting the behaviour of the cranial neural crest during development with the venerable, perhaps incorrect, view that gill-supporting cartilages of an ancient agnathan evolved into the skeleton of an early gnathostome's jaw. We discuss the pattern of migration of the cranial neural crest ectomesenchyme in zebrafish, along with the subsequent arrangement of postmigratory crest and head mesoderm in the nascent pharyngeal segments (branchiomeres), in diverse gnathostomes and in lampreys. These characteristics provide for a plausible von Baerian explanation for the problematic inside-outside change in topology of the gills and their supports between these 2 major groups of vertebrates. We consider it likely that the jaw supports did indeed arise from branchiomeric cartilages.

  10. Flow characteristics at trapezoidal broad-crested side weir

    Directory of Open Access Journals (Sweden)

    Říha Jaromír

    2015-06-01

    Full Text Available Broad-crested side weirs have been the subject of numerous hydraulic studies; however, the flow field at the weir crest and in front of the weir in the approach channel still has not been fully described. Also, the discharge coefficient of broad-crested side weirs, whether slightly inclined towards the stream or lateral, still has yet to be clearly determined. Experimental research was carried out to describe the flow characteristics at low Froude numbers in the approach flow channel for various combinations of in- and overflow discharges. Three side weir types with different oblique angles were studied. Their flow characteristics and discharge coefficients were analyzed and assessed based on the results obtained from extensive measurements performed on a hydraulic model. The empirical relation between the angle of side weir obliqueness, Froude numbers in the up- and downstream channels, and the coefficient of obliqueness was derived.

  11. Iliac Crest Avulsion Fracture in a Young Sprinter.

    Science.gov (United States)

    Casabianca, L; Rousseau, R; Loriaut, P; Massein, A; Mirouse, G; Gerometta, A; Khiami, F

    2015-01-01

    Avulsion fracture of the iliac crest is an uncommon pathology. It usually occurs in teenagers during sport activities, more common in boys. We report a case of 16-year-old male competitive sprinter, who had an avulsion of a part of the iliac crest and the anterior-superior iliac spine during a competition. The traumatism occurred during the period of acceleration phase out of the blocks which corresponds to the maximum traction phase on the tendons. Then a total loss of function of the lower limb appears forcing him to stop the run. X-ray and CT scan confirmed the rare diagnosis of avulsion of the quasitotality of the iliac crest apophysis, corresponding to Salter 2 fracture. We performed an open reduction and internal fixation with two screws, allowing a return to sport after 3 months and his personal best record in the 100 meters at the 6th postoperative month.

  12. Iliac Crest Avulsion Fracture in a Young Sprinter

    Directory of Open Access Journals (Sweden)

    L. Casabianca

    2015-01-01

    Full Text Available Avulsion fracture of the iliac crest is an uncommon pathology. It usually occurs in teenagers during sport activities, more common in boys. We report a case of 16-year-old male competitive sprinter, who had an avulsion of a part of the iliac crest and the anterior-superior iliac spine during a competition. The traumatism occurred during the period of acceleration phase out of the blocks which corresponds to the maximum traction phase on the tendons. Then a total loss of function of the lower limb appears forcing him to stop the run. X-ray and CT scan confirmed the rare diagnosis of avulsion of the quasitotality of the iliac crest apophysis, corresponding to Salter 2 fracture. We performed an open reduction and internal fixation with two screws, allowing a return to sport after 3 months and his personal best record in the 100 meters at the 6th postoperative month.

  13. Current Situation and Demand of Rural Endowment Security in Shaanxi Province

    Institute of Scientific and Technical Information of China (English)

    Chunmei; LIU; Lutang; LI

    2013-01-01

    With intensification of population aging and rise in elderly dependency ratio,the demand for endowment security becomes higher and higher,particularly in rural areas.Taking Shaanxi Province as an example,the authors selected people older than 65 in 18 natural villages in north Shaanxi,south Shaanxi and Guanzhong.With the aid of survey data and related official statistical data,they made an evaluation of current situation of the rural endowment security in Shaanxi Province.Results indicate that home-based endowment is the major endowment method of rural elderly,but such method is influenced by family’s economic support ability and children’s support willingness,thus facing big demand gap.On the basis of analyzing gap problem,the authors recommended that government should increase financial and policy supports,optimize management and monitoring,actively develop non-government organizations,and promote socialization of rural endowment service.

  14. Distinct functional and temporal requirements for zebrafish Hdac1 during neural crest-derived craniofacial and peripheral neuron development.

    Directory of Open Access Journals (Sweden)

    Myron S Ignatius

    Full Text Available The regulation of gene expression is accomplished by both genetic and epigenetic means and is required for the precise control of the development of the neural crest. In hdac1(b382 mutants, craniofacial cartilage development is defective in two distinct ways. First, fewer hoxb3a, dlx2 and dlx3-expressing posterior branchial arch precursors are specified and many of those that are consequently undergo apoptosis. Second, in contrast, normal numbers of progenitors are present in the anterior mandibular and hyoid arches, but chondrocyte precursors fail to terminally differentiate. In the peripheral nervous system, there is a disruption of enteric, DRG and sympathetic neuron differentiation in hdac1(b382 mutants compared to wildtype embryos. Specifically, enteric and DRG-precursors differentiate into neurons in the anterior gut and trunk respectively, while enteric and DRG neurons are rarely present in the posterior gut and tail. Sympathetic neuron precursors are specified in hdac1(b382 mutants and they undergo generic neuronal differentiation but fail to undergo noradrenergic differentiation. Using the HDAC inhibitor TSA, we isolated enzyme activity and temporal requirements for HDAC function that reproduce hdac1(b382 defects in craniofacial and sympathetic neuron development. Our study reveals distinct functional and temporal requirements for zebrafish hdac1 during neural crest-derived craniofacial and peripheral neuron development.

  15. Iris sector heterochromia as a marker for neural crest disease.

    Science.gov (United States)

    Brazel, S M; Sullivan, T J; Thorner, P S; Clarke, M P; Hunter, W S; Morin, J D

    1992-02-01

    A 6-month-old female infant with biopsy-proved Hirschsprung's disease had associated sector heterochromia of the irides. The association between sector heterochromia and Hirschsprung's disease has been previously reported and both conditions have been ascribed to neural crest defects. Histologic characteristics of the ocular involvement have not previously been reported, to our knowledge. Histopathologic examination of the globes revealed decreased iris stroma, decreased pigmentation in the anterior stroma, and reduced numbers of pigment-producing cells in the affected areas. Both the ocular and gastrointestinal findings reflect abnormalities in tissues of neural crest origin.

  16. 34 CFR 628.46 - How shall a grantee calculate the amount of endowment fund income that it may withdraw and spend?

    Science.gov (United States)

    2010-07-01

    ... ENDOWMENT CHALLENGE GRANT PROGRAM What Conditions Must a Grantee Meet Under the Endowment Challenge Grant..., it must— (1) Determine the value of endowment fund income by subtracting the endowment fund corpus from the current total value of the endowment fund on that date; and (2) Calculate the amount...

  17. Mesenchymal progenitor cells for the osteogenic lineage.

    Science.gov (United States)

    Ono, Noriaki; Kronenberg, Henry M

    2015-09-01

    Mesenchymal progenitors of the osteogenic lineage provide the flexibility for bone to grow, maintain its function and homeostasis. Traditionally, colony-forming-unit fibroblasts (CFU-Fs) have been regarded as surrogates for mesenchymal progenitors; however, this definition cannot address the function of these progenitors in their native setting. Transgenic murine models including lineage-tracing technologies based on the cre-lox system have proven to be useful in delineating mesenchymal progenitors in their native environment. Although heterogeneity of cell populations of interest marked by a promoter-based approach complicates overall interpretation, an emerging complexity of mesenchymal progenitors has been revealed. Current literatures suggest two distinct types of bone progenitor cells; growth-associated mesenchymal progenitors contribute to explosive growth of bone in early life, whereas bone marrow mesenchymal progenitors contribute to the much slower remodeling process and response to injury that occurs mainly in adulthood. More detailed relationships of these progenitors need to be studied through further experimentation.

  18. Expression of chondrogenic potential of mouse trunk neural crest cells by FGF2 treatment.

    Science.gov (United States)

    Ido, Atsushi; Ito, Kazuo

    2006-02-01

    There is a significant difference between the developmental patterns of cranial and trunk neural crest cells in the amniote. Thus, whereas cranial neural crest cells generate bone and cartilage, trunk neural crest cells do not contribute to skeletal derivatives. We examined whether mouse trunk neural crest cells can undergo chondrogenesis to analyze how the difference between the developmental patterns of cranial and trunk neural crest cells arises. Our present data demonstrate that mouse trunk neural crest cells have chondrogenic potential and that fibroblast growth factor (FGF) 2 is an inducing factor for their chondrogenesis in vitro. FGF2 altered the expression patterns of Hox9 genes and Id2, a cranial neural crest cell marker. These results suggest that environmental cues may play essential roles in generating the difference between developmental patterns of cranial and trunk neural crest cells. Copyright 2005 Wiley-Liss, Inc.

  19. Migrating neural crest cells in the trunk of the avian embryo are multipotent

    OpenAIRE

    Fraser, Scott E.; Bronner-Fraser, Marianne

    1991-01-01

    Trunk neural crest cells migrate extensively and give rise to diverse cell types, including cells of the sensory and autonomic nervous systems. Previously, we demonstrated that many premigratory trunk neural crest cells give rise to descendants with distinct phenotypes in multiple neural crest derivatives. The results are consistent with the idea that neural crest cells are multipotent prior to their emigration from the neural tube and become restricted in phenotype after leaving the neural t...

  20. New data on thermal flow in the Kolbensei crest region

    Energy Technology Data Exchange (ETDEWEB)

    Polyak, B.G.; Smirnov, Ya.B.; Merkushov, V.N.; Paduchikh, V.I.; Podgornykh, L.V.

    1978-11-01

    Results are given for measurements made of the geothermal gradient in the bottom sediment of the Kolbensei crest region of the Greenland Sea. Data are given for thermal flow measurements made at 12 stations positioned along the axial portion of the Kolbensei crest and transversely to its course. Diagrams are given illustrating the positioning of the thermal flow stations and the thermal flow along the profile as well as the energy effect of geothermal activity along the cross-section of the crest. An analysis of the experimental data indicates that the central zone of the Middle Atlantic crest north of Iceland and the active rift zones of the island exhibit the same energy profile which is indicative of their identical deep dynamic processes. The total heat loss in the active rift zones was found to be about 10.10/sup -6/ cal/cm/sup 2/.sec, and is pooled from the conductive thermal flow and convective thermal withdrawal by magma and thermal springs. 10 references, 2 figures, 1 table.

  1. Wave transmission at low-crested structures using neural networks

    NARCIS (Netherlands)

    Van Oosten, R.P.; Peixó Marco, J.; Van der Meer, J.W.; Van Gent, M.; Verhagen, H.J.

    2006-01-01

    The European Union funded project DELOS was focused on wave transmission and an extensive database on low-crested rubble mound structures was generated. During DELOS, new empirical wave transmission formulae were derived. These formulae still showed a considerable scatter due to a limited number of

  2. The CREST reactive-burn model for explosives

    Directory of Open Access Journals (Sweden)

    Maheswaran M-A.

    2011-01-01

    Full Text Available CREST is an innovative reactive-burn model that has been developed at AWE for simulating shock initiation and detonation propagation behaviour in explosives. The model has a different basis from other reactive-burn models in that its reaction rate is independent of local flow variables behind the shock wave e.g. pressure and temperature. The foundation for CREST, based on a detailed analysis of data from particle-velocity gauge experiments, is that the reaction rate depends only on the local shock strength and the time since the shock passed. Since a measure of shock strength is the entropy of the non-reacted explosive, which remains constant behind a shock, CREST uses an entropy-dependent reaction rate. This paper will provide an overview of the CREST model and its predictive capability. In particular, it will be shown that the model can predict a wide range of experimental phenomena for both shock initiation (e.g. the effects of porosity and initial temperature on sustained-shock and thin-flyer initiation and detonation propagation (e.g. the diameter effect curve and detonation failure cones using a single set of coefficients.

  3. DNA methyltransferase 3b is dispensable for mouse neural crest development.

    Directory of Open Access Journals (Sweden)

    Bridget T Jacques-Fricke

    Full Text Available The neural crest is a population of multipotent cells that migrates extensively throughout vertebrate embryos to form diverse structures. Mice mutant for the de novo DNA methyltransferase DNMT3b exhibit defects in two neural crest derivatives, the craniofacial skeleton and cardiac ventricular septum, suggesting that DNMT3b activity is necessary for neural crest development. Nevertheless, the requirement for DNMT3b specifically in neural crest cells, as opposed to interacting cell types, has not been determined. Using a conditional DNMT3b allele crossed to the neural crest cre drivers Wnt1-cre and Sox10-cre, neural crest DNMT3b mutants were generated. In both neural crest-specific and fully DNMT3b-mutant embryos, cranial neural crest cells exhibited only subtle migration defects, with increased numbers of dispersed cells trailing organized streams in the head. In spite of this, the resulting cranial ganglia, craniofacial skeleton, and heart developed normally when neural crest cells lacked DNMT3b. This indicates that DNTM3b is not necessary in cranial neural crest cells for their development. We conclude that defects in neural crest derivatives in DNMT3b mutant mice reflect a requirement for DNMT3b in lineages such as the branchial arch mesendoderm or the cardiac mesoderm that interact with neural crest cells during formation of these structures.

  4. 34 CFR 628.44 - When and for what purposes may a grantee use the endowment fund corpus?

    Science.gov (United States)

    2010-07-01

    ... endowment fund corpus? 628.44 Section 628.44 Education Regulations of the Offices of the Department of... for what purposes may a grantee use the endowment fund corpus? (a)(1) During the grant period, a grantee may not withdraw or spend any part of the endowment fund corpus. (2) If, during the grant...

  5. A Comparative Experimental Study of Wave Forces on a Vertical Cylinder in Long-Crested and Short-Crested Seas

    DEFF Research Database (Denmark)

    Frigaard, Peter; Burcharth, Hans F.

    1988-01-01

    An experimental study is carried out to investigate the wave forces on a slender cylinder. Special attention is given to the wave forces in the surface zone and correlation of forces along the cylinder. The experiments consider the effects of both long and short-crested irregular waves....

  6. GEORG-SCHMORL-PRIZE OF THE GERMAN SPINE SOCIETY (DWG) 2016: Comparison of in vitro osteogenic potential of iliac crest and degenerative facet joint bone autografts for intervertebral fusion in lumbar spinal stenosis.

    Science.gov (United States)

    Geurts, Jeroen; Ramp, Daniela; Schären, Stefan; Netzer, Cordula

    2017-05-01

    The promotion of spinal fusion using bone autografts is largely mediated by the osteoinductive potential of progenitors/mesenchymal stem cells (MSC) that reside in the marrow spaces of cancellous bone. Iliac crest is the common autograft donor site, but its use presents an increased risk for donor site pain, morbidity and infection. Degenerative bone samples harvested during facetectomy might provide an alternative viable source of osteoinductive autografts. In this study, we conducted an intra-individual comparison of the osteogenic potential of isolated low passage MSC from both sources. Iliac crest and degenerative facet joints were harvested from eight consecutive patients undergoing transforaminal lumbar interspinal fusion due to lumbar spinal stenosis. MSC were isolated by collagenase digestion, selected by plastic adherence and minimally expanded for downstream assays. Clonogenic and osteogenic potential was evaluated by colony formation assays in control and osteogenic culture medium. Osteogenic properties, including alkaline phosphatase (ALP) induction, matrix mineralization and type I collagen mRNA and protein expression were characterized using quantitative histochemical staining and reverse transcription PCR. Spontaneous adipogenesis was analysed by adipocyte enumeration and gene expression analysis of adipogenic markers. Average colony-forming efficiency in osteogenic medium was equal between iliac crest (38 ± 12%) and facet joint (36 ± 11%). Osteogenic potential at the clonal level was 55 ± 26 and 68 ± 17% for iliac crest and facet joint MSC, respectively. Clonogenic and osteogenic potential were significantly negatively associated with donor age. Osteogenic differentiation led to significant induction of ALP activity in iliac crest (sixfold) and facet joint (eightfold) MSC. Matrix mineralization quantified by Alizarin red staining was increased by osteogenic differentiation, yet similar between both MSC sources. Protein expression of type

  7. Thin hard crest on the edge of ceramic acetabular liners accelerates wear in edge loading.

    Science.gov (United States)

    Sanders, Anthony P; Dudhiya, Parth J; Brannon, Rebecca M

    2012-01-01

    Ceramic acetabular liners may exhibit a small, sharp crest-an artifact of discontinuous machining steps--at the junction between the concave spherical surface and the interior edge. On 3 ceramic liners, this crest was found to form a 9° to 11° deviation from tangency. Edge loading wear tests were conducted directly on this crest and on a smoother region of the edge. The crest elicited 2 to 15 times greater volumetric wear on the femoral head. The propensity of the crest to rapidly (machining protocols might be a root cause of stripe wear and squeaking in ceramic acetabular bearings.

  8. Possible promotion of neuronal differentiation in fetal rat brain neural progenitor cells after sustained exposure to static magnetism.

    Science.gov (United States)

    Nakamichi, Noritaka; Ishioka, Yukichi; Hirai, Takao; Ozawa, Shusuke; Tachibana, Masaki; Nakamura, Nobuhiro; Takarada, Takeshi; Yoneda, Yukio

    2009-08-15

    We have previously shown significant potentiation of Ca(2+) influx mediated by N-methyl-D-aspartate receptors, along with decreased microtubules-associated protein-2 (MAP2) expression, in hippocampal neurons cultured under static magnetism without cell death. In this study, we investigated the effects of static magnetism on the functionality of neural progenitor cells endowed to proliferate for self-replication and differentiate into neuronal, astroglial, and oligodendroglial lineages. Neural progenitor cells were isolated from embryonic rat neocortex and hippocampus, followed by culture under static magnetism at 100 mT and subsequent determination of the number of cells immunoreactive for a marker protein of particular progeny lineages. Static magnetism not only significantly decreased proliferation of neural progenitor cells without affecting cell viability, but also promoted differentiation into cells immunoreactive for MAP2 with a concomitant decrease in that for an astroglial marker, irrespective of the presence of differentiation inducers. In neural progenitors cultured under static magnetism, a significant increase was seen in mRNA expression of several activator-type proneural genes, such as Mash1, Math1, and Math3, together with decreased mRNA expression of the repressor type Hes5. These results suggest that sustained static magnetism could suppress proliferation for self-renewal and facilitate differentiation into neurons through promoted expression of activator-type proneural genes by progenitor cells in fetal rat brain.

  9. Aerodynamic Characteristics of the Crest with Membrane Attachment on Cretaceous Pterodactyloid Nyctosaurus

    Institute of Scientific and Technical Information of China (English)

    XING Lida; WU Jianghao; LU Yi; L(U) Junchang; JI Qiang

    2009-01-01

    The Nyctosaurus specimen KJ1 was reconstructed under the hypothesis that there is a membrane attached to the crest;the so-called headsail crest.The aerodynamic forces and moment acting on the headsail crest were analyzed.It was shown that KJ1 might adjust the angle of the headsail crest relative to the air current as one way to generate thrust(one of the aerodynamic forces,used to overcome body drag in forward flight)and that the magnitude of the thrust and moment could vary with the gesture angle and the relative locafion between the aerodynamic center of the headsail crest and body's center of gravity.Three scenarios were tested for comparison:the crest with membrane attachment,the crest without membrane attachment and the absence of a cranial crest.It was shown that the aerodynamic characteristics(increasing.maintaining and decreasing thrusts and moment) would have almost disappear in flight for the crest without membrane attachment and Was non-existent without the cranial crest.It is suggested from aerodynamics evidence alone that Nyctosaurus specimen KJ1 had a membrane attached to the crest and used this reconstructed form for auxiliary flight control.

  10. Draxin, an axon guidance protein, affects chick trunk neural crest migration.

    Science.gov (United States)

    Su, Yuhong; Naser, Iftekhar B; Islam, Shahidul M; Zhang, Sanbing; Ahmed, Giasuddin; Chen, Sandy; Shinmyo, Yohei; Kawakami, Minoru; Yamamura, Ken-ichi; Tanaka, Hideaki

    2009-12-01

    The neural crest is a multipotent population of migratory cells that arises in the central nervous system and subsequently migrates along defined stereotypic pathways. In the present work, we analyzed the role of a repulsive axon guidance protein, draxin, in the migration of neural crest cells. Draxin is expressed in the roof plate of the chick trunk spinal cord and around the early migration pathway of neural crest cells. Draxin modulates chick neural crest cell migration in vitro by reducing the polarization of these cells. When exposed to draxin, the velocity of migrating neural crest cells was reduced, and the cells changed direction so frequently that the net migration distance was also reduced. Overexpression of draxin also caused some early migrating neural crest cells to change direction to the dorsolateral pathway in the chick trunk region, presumably due to draxin's inhibitory activity. These results demonstrate that draxin, an axon guidance protein, can also affect trunk neural crest migration in the chick embryo.

  11. Hydraulic Evaluation of the Crest Wing Wave Energy Converter

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Antonishen, Michael Patrick

    This report presents the results of an experimental study of the wave energy converting abilities of the Crest Wing wave energy converter (WEC). The Crest Wing is a WEC that uses its movement in matching the shape of an oncoming wave to generate power. Model tests have been performed using a scale...... model (length scale 1:30), provided by WaveEnergyFyn, in regular and irregular wave states that can be found in Assessment of Wave Energy Devices. Best Practice as used in Denmark (Frigaard et al., 2008). The tests were carried out at Dept. of Civil Engineering, Aalborg (Frigaard et al., 2008......). The tests were carried out at Dept. of Civil Engineering, Aalborg University (AAU) in the 3D deep water wave tank. The displacement and force applied to a power take off system, provided by WaveEnergyFyn, were measured and used to calculate total power take off....

  12. Numerical analysis of divertor plasma for demo-CREST

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, M.; Maeki, K.; Hatayama, A. [Graduate School of Fundamental Science and Technology, Keio University, Yokohama (Japan); Hiwatari, R. [Central Research Institute of Electric Power Industry (CRIEPI), Tokyo (Japan); Bonnin, X. [LIMHP-CNRS, Universite Paris 13, Villetaneuse (France); Zhu, S. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Schneider, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Greifswald (Germany); Coster, D. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany)

    2010-05-15

    The numerical analysis of the demonstration fusion reactor Demo-CREST has been carried out; this analysis focuses on impurity seeding. Several design activities for DEMO have been carried out; however, its detailed divertor plasma analysis remains to be carried out. Therefore, in this study, we discuss the possibility of neon puffing in demo-CREST to decrease the power load to the divertor plate by using the B2-EIRENE code. It has been shown that the radiation power loss by neon increases with upstream plasma density and that the peak power load to the divertor plate comes close to the allowable level by using the preliminary divertor configuration (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. File list: DNS.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.20.AllAg.hESC_derived_neural_crests hg19 DNase-seq Pluripotent stem cell hESC derived neural crest...s http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.20.AllAg.hESC_derived_neural_crests.bed ...

  14. File list: DNS.PSC.10.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.10.AllAg.hESC_derived_neural_crests hg19 DNase-seq Pluripotent stem cell hESC derived neural crest...s http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.10.AllAg.hESC_derived_neural_crests.bed ...

  15. File list: DNS.PSC.05.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.05.AllAg.hESC_derived_neural_crests hg19 DNase-seq Pluripotent stem cell hESC derived neural crest...s http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.05.AllAg.hESC_derived_neural_crests.bed ...

  16. File list: DNS.PSC.50.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.50.AllAg.hESC_derived_neural_crests hg19 DNase-seq Pluripotent stem cell hESC derived neural crest...s http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.50.AllAg.hESC_derived_neural_crests.bed ...

  17. Environmental correlates of breeding in the Crested Caracara (Caracara Cheriway)

    Science.gov (United States)

    Morrison, J.L.; Pias, Kyle E.; Cohen, J.B.; Catlin, D.H.

    2009-01-01

    We evaluated the influence of weather on reproduction of the Crested Caracara (Caracara cheriway) in an agricultural landscape in south-central Florida. We used a mixed logistic-regression modeling approach within an information-theoretic framework to examine the influence of total rainfall, rainfall frequency, and temperature on the number of breeding pairs, timing of breeding, nest success, and productivity of Crested Caracaras during 1994-2000. The best models indicated an influence of rainfall frequency and laying period on reproduction. More individuals nested and more pairs nested earlier during years with more frequent rainfall in late summer and early fall. Pairs that nested later in each breeding season had smaller clutches, lower nest success and productivity, and higher probability of nest failure. More frequent rainfall during early spring months that are usually characterized by water deficit (March-May), more frequent rainfall during the fall drawdown period (September-November), and a shorter winter dry period showed some association with higher probability of brood reduction and lower nest success. The proportion of nests that failed was higher in "wet" years, when total rainfall during the breeding season (September-April) was >10% above the 20-year average. Rainfall may influence reproduction in Crested Caracaras indirectly through food resources. As total rainfall increased during February-April, when most pairs are feeding nestlings or dependent fledglings, the proportion of drawdown-dependent species (those that become available as rainfall decreases and wetlands become isolated and shallow) in the diet of Crested Caracaras declined, which may indicate reduced availability of foraging habitat for this primarily terrestrial raptor. ?? The American Ornithologists' Union, 2009.

  18. Medical image of the week: CREST plus ILD

    OpenAIRE

    Oliva I; Knox KS

    2013-01-01

    A 60 year old female with a history of fibromyalgia presented with dyspnea and skin changes, predominantly on the hands. Physical exam and imaging showed classic findings of limited cutaneous systemic sclerosis (scleroderma) CREST syndrome. Calcinosis cutis (Figure 1A), Raynaud’s (not shown but endorsed by the patient), Esophageal dysmotility (Figure 1B, dilated esophagus), Sclerodactyly (Figure 1C), and Teleganectasias (Figure 1D) were all present. Ground glass opacities were seen predomi...

  19. Generating trunk neural crest from human pluripotent stem cells

    OpenAIRE

    Miller Huang; Matthew L. Miller; McHenry, Lauren K.; Tina Zheng; Qiqi Zhen; Shirin Ilkhanizadeh; Conklin, Bruce R.; Bronner, Marianne E.; Weiss, William A.

    2016-01-01

    Neural crest cells (NCC) are stem cells that generate different lineages, including neuroendocrine, melanocytic, cartilage, and bone. The differentiation potential of NCC varies according to the level from which cells emerge along the neural tube. For example, only anterior “cranial” NCC form craniofacial bone, whereas solely posterior “trunk” NCC contribute to sympathoadrenal cells. Importantly, the isolation of human fetal NCC carries ethical and scientific challenges, as NCC induction typi...

  20. Scleroderma and CREST syndrome: a case report in dentistry.

    Science.gov (United States)

    Lauritano, D; Bussolati, A; Baldoni, M; Leonida, A

    2011-09-01

    CREST syndrome is part of the heterogeneous scleroderma group of autoimmune diseases that cause thickening, hardening and tightening of the connective tissue in different parts of the body, and it may lead to complex disorders. CREST syndrome is characterized by the coexistence of calcinosis, Raynaud's phenomenon, esophageal hypomotility, sclerodactily and telangectasia. A 72-year-old caucasian woman is referred to the S. Gerardo Hospital of Monza, with a chief complaint of oral pain and difficulties in deglutition and eating, associated with denture instability and difficulties to fit it. She had been previously diagnosed with Raynaud's phenomenon, and afterwards with CREST syndrome. Extra-oral examination underlined taut, thickened and rigid skin, pallid-red irregular maculae all over the face, telangiectasias and acrocyanosis. Intra-oral examination showed no alteration of the mucosa, but we can observe tongue rigidity and some speckled red alternating with white spots on the hard palate and in the vestibule. We undermitted the patient the dental treatment of Sjogren's syndrome. The management of the Sjogren's syndrome is symptomatic and empirical, and involves the use of saliva secretion stimulators, salivary substitutes and coadjuvants. Dental treatment and prophylaxis are important to prevent the consequences of xerostomia, such as rampant caries, based on the administration of topical fluoride in toothpastes and rinses, and supplemented by fluoride gels and varnishes. Instruction and reinforcement of oral hygiene, along with frequent dental assessment and management by the dentist are essential measures to preserve the oral health of those affected with CREST syndrome in progression to SS, complicated with Sjogren's syndrome.

  1. Chicken trunk neural crest migration visualized with HNK1.

    Science.gov (United States)

    Giovannone, Dion; Ortega, Blanca; Reyes, Michelle; El-Ghali, Nancy; Rabadi, Maes; Sao, Sothy; de Bellard, Maria Elena

    2015-04-01

    The development of the nervous system involves cells remaining within the neural tube (CNS) and a group of cells that delaminate from the dorsal neural tube and migrate extensively throughout the developing embryo called neural crest cells (NCC). These cells are a mesenchymal highly migratory group of cells that give rise to a wide variety of cell derivatives: melanocytes, sensory neurons, bone, Schwann cells, etc. But not all NCC can give rise to all derivatives, they have fate restrictions based on their axial level of origin: cranial, vagal, trunk and sacral. Our aim was to provide a thorough presentation on how does trunk neural crest cell migration looks in the chicken embryo, in wholemount and in sections using the unique chicken marker HNK1. The description presented here makes a good guideline for those interested in viewing trunk NCC migration patterns. We show how before HH14 there are few trunk NCC delaminating and migrating, but between HH15 through HH19 trunk NCC delaminate in large numbers. Melanocytes precursors begin to enter the dorsolateral pathway by HH17. We found that by HH20 HNK1 is not a valid good marker for NCC and that HNK1 is a better marker than Sox10 when looking at neural crest cells morphology and migration details. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

  2. Hematopoietic Stem Cells in Neural-crest Derived Bone Marrow.

    Science.gov (United States)

    Jiang, Nan; Chen, Mo; Yang, Guodong; Xiang, Lusai; He, Ling; Hei, Thomas K; Chotkowski, Gregory; Tarnow, Dennis P; Finkel, Myron; Ding, Lei; Zhou, Yanheng; Mao, Jeremy J

    2016-12-21

    Hematopoietic stem cells (HSCs) in the endosteum of mesoderm-derived appendicular bones have been extensively studied. Neural crest-derived bones differ from appendicular bones in developmental origin, mode of bone formation and pathological bone resorption. Whether neural crest-derived bones harbor HSCs is elusive. Here, we discovered HSC-like cells in postnatal murine mandible, and benchmarked them with donor-matched, mesoderm-derived femur/tibia HSCs, including clonogenic assay and long-term culture. Mandibular CD34 negative, LSK cells proliferated similarly to appendicular HSCs, and differentiated into all hematopoietic lineages. Mandibular HSCs showed a consistent deficiency in lymphoid differentiation, including significantly fewer CD229 + fractions, PreProB, ProB, PreB and B220 + slgM cells. Remarkably, mandibular HSCs reconstituted irradiated hematopoietic bone marrow in vivo, just as appendicular HSCs. Genomic profiling of osteoblasts from mandibular and femur/tibia bone marrow revealed deficiencies in several HSC niche regulators among mandibular osteoblasts including Cxcl12. Neural crest derived bone harbors HSCs that function similarly to appendicular HSCs but are deficient in the lymphoid lineage. Thus, lymphoid deficiency of mandibular HSCs may be accounted by putative niche regulating genes. HSCs in craniofacial bones have functional implications in homeostasis, osteoclastogenesis, immune functions, tumor metastasis and infections such as osteonecrosis of the jaw.

  3. Bed profile downstream compound sharp crested V-notch weir

    Directory of Open Access Journals (Sweden)

    Mohammad Mahmoud Ibrahim

    2015-09-01

    Full Text Available Triangular weirs are commonly used to measure discharge in open channel flow. They represent an inexpensive, reliable methodology to monitor water allocation. A compound sharp-crested weir consisting of two triangular parts with different notch angles was used. The lower triangular part of the weir handles the normal range of discharges while the upper part measures the higher peak flows. This paper evaluates experimentally the local scour downstream compound sharp crested V-notch weir. Forty-eight (48 experimental runs were conducted. Three models of weirs with different geometries (combination of notch angles, four upstream water levels, three water levels at the tailgate, and two bed materials were used. Multiple regression equations based on energy principal and dimensional analysis theory were deduced to estimate the local scour downstream of the weir models. The developed equations were compared with the experimental data. The comparison between the local scour downstream classical V-notch weir and a compound sharp-crested weir consisting of two triangular parts with different notch angles was found to be unnoticed. The study recommended using the compound V-notch weir to pass high discharges instead of the classical V-notch weir.

  4. MR imaging findings of medial tibial crest friction

    Energy Technology Data Exchange (ETDEWEB)

    Klontzas, Michail E., E-mail: miklontzas@gmail.com; Akoumianakis, Ioannis D., E-mail: ioannis.akoumianakis@gmail.com; Vagios, Ilias, E-mail: iliasvagios@gmail.com; Karantanas, Apostolos H., E-mail: akarantanas@gmail.com

    2013-11-01

    Objective: Medial tibial condyle bone marrow edema (BME), associated with soft tissue edema (STe) surrounding the medial collateral ligament, was incidentally observed in MRI examinations of young and athletic individuals. The aim of the present study was to 1. Prospectively investigate the association between these findings and coexistence of localized pain, and 2. Explore the possible contribution of the tibial morphology to its pathogenesis. Methods: The medial tibial condyle crest was evaluated in 632 knee MRI examinations. The angle and depth were measured by two separate evaluators. The presence of STe and BME was recorded. A third evaluator blindly assessed the presence of pain at this site. Results: BME associated with STe was found in 24 patients (with no history of previous trauma, osteoarthritis, tumor or pes anserine bursitis). The mean crest angle was 151.3° (95%CI 147.4–155.3°) compared to 159.4° (95%CI 158.8–160°) in controls (Mann–Whitney test, P < 0.0001). MRI findings were highly predictive of localized pain (sensitivity 92% specificity 99%, Fisher's exact test, P < 0.0001). Conclusion: Friction at the medial tibial condyle crest is a painful syndrome. MRI is a highly specific and sensitive imaging modality for its diagnosis.

  5. Periodontal Bioengineering: A Discourse in Surface Topographies, Progenitor Cells and Molecular Profiles

    Science.gov (United States)

    Dangaria, Smit J.

    2011-12-01

    Stem/progenitor cells are a population of cells capable of providing replacement cells for a given differentiated cell type. We have applied progenitor cell-based technologies to generate novel tissue-engineered implants that use biomimetic strategies with the ultimate goal of achieving full regeneration of lost periodontal tissues. Mesenchymal periodontal tissues such as cementum, alveolar bone (AB), and periodontal ligament (PDL) are neural crest-derived entities that emerge from the dental follicle (DF) at the onset of tooth root formation. Using a systems biology approach we have identified key differences between these periodontal progenitors on the basis of global gene expression profiles, gene cohort expression levels, and epigenetic modifications, in addition to differences in cellular morphologies. On an epigenetic level, DF progenitors featured high levels of the euchromatin marker H3K4me3, whereas PDL cells, AB osteoblasts, and cementoblasts contained high levels of the transcriptional repressor H3K9me3. Secondly, we have tested the influence of natural extracellular hydroxyapatite matrices on periodontal progenitor differentiation. Dimension and structure of extracellular matrix surfaces have powerful influences on cell shape, adhesion, and gene expression. Here we show that natural tooth root topographies induce integrin-mediated extracellular matrix signaling cascades in tandem with cell elongation and polarization to generate physiological periodontium-like tissues. In this study we replanted surface topography instructed periodontal ligament progenitors (PDLPs) into rat alveolar bone sockets for 8 and 16 weeks, resulting in complete attachment of tooth roots to the surrounding alveolar bone with a periodontal ligament fiber apparatus closely matching physiological controls along the entire root surface. Displacement studies and biochemical analyses confirmed that progenitor-based engineered periodontal tissues were similar to control teeth and

  6. The development of zebrafish tendon and ligament progenitors.

    Science.gov (United States)

    Chen, Jessica W; Galloway, Jenna L

    2014-05-01

    Despite the importance of tendons and ligaments for transmitting movement and providing stability to the musculoskeletal system, their development is considerably less well understood than that of the tissues they serve to connect. Zebrafish have been widely used to address questions in muscle and skeletal development, yet few studies describe their tendon and ligament tissues. We have analyzed in zebrafish the expression of several genes known to be enriched in mammalian tendons and ligaments, including scleraxis (scx), collagen 1a2 (col1a2) and tenomodulin (tnmd), or in the tendon-like myosepta of the zebrafish (xirp2a). Co-expression studies with muscle and cartilage markers demonstrate the presence of scxa, col1a2 and tnmd at sites between the developing muscle and cartilage, and xirp2a at the myotendinous junctions. We determined that the zebrafish craniofacial tendon and ligament progenitors are neural crest derived, as in mammals. Cranial and fin tendon progenitors can be induced in the absence of differentiated muscle or cartilage, although neighboring muscle and cartilage are required for tendon cell maintenance and organization, respectively. By contrast, myoseptal scxa expression requires muscle for its initiation. Together, these data suggest a conserved role for muscle in tendon development. Based on the similarities in gene expression, morphology, collagen ultrastructural arrangement and developmental regulation with that of mammalian tendons, we conclude that the zebrafish tendon populations are homologous to their force-transmitting counterparts in higher vertebrates. Within this context, the zebrafish model can be used to provide new avenues for studying tendon biology in a vertebrate genetic system.

  7. Dual function of Slit2 in repulsion and enhanced migration of trunk, but not vagal, neural crest cells

    OpenAIRE

    De Bellard, Maria Elena; Rao, Yi; Bronner-Fraser, Marianne

    2003-01-01

    Neural crest precursors to the autonomic nervous system form different derivatives depending upon their axial level of origin; for example, vagal, but not trunk, neural crest cells form the enteric ganglia of the gut. Here, we show that Slit2 is expressed at the entrance of the gut, which is selectively invaded by vagal, but not trunk, neural crest. Accordingly, only trunk neural crest cells express Robo receptors. In vivo and in vitro experiments demonstrate that trunk, not vagal, crest cell...

  8. Migration pathways of sacral neural crest during development of lower urogenital tract innervation.

    Science.gov (United States)

    Wiese, Carrie B; Deal, Karen K; Ireland, Sara J; Cantrell, V Ashley; Southard-Smith, E Michelle

    2017-09-01

    The migration and fate of cranial and vagal neural crest-derived progenitor cells (NCPCs) have been extensively studied; however, much less is known about sacral NCPCs particularly in regard to their distribution in the urogenital system. To construct a spatiotemporal map of NCPC migration pathways into the developing lower urinary tract, we utilized the Sox10-H2BVenus transgene to visualize NCPCs expressing Sox10. Our aim was to define the relationship of Sox10-expressing NCPCs relative to bladder innervation, smooth muscle differentiation, and vascularization through fetal development into adulthood. Sacral NCPC migration is a highly regimented, specifically timed process, with several potential regulatory mileposts. Neuronal differentiation occurs concomitantly with sacral NCPC migration, and neuronal cell bodies are present even before the pelvic ganglia coalesce. Sacral NCPCs reside within the pelvic ganglia anlagen through 13.5 days post coitum (dpc), after which they begin streaming into the bladder body in progressive waves. Smooth muscle differentiation and vascularization of the bladder initiate prior to innervation and appear to be independent processes. In adult bladder, the majority of Sox10+ cells express the glial marker S100β, consistent with Sox10 being a glial marker in other tissues. However, rare Sox10+ NCPCs are seen in close proximity to blood vessels and not all are S100β+, suggesting either glial heterogeneity or a potential nonglial role for Sox10+ cells along vasculature. Taken together, the developmental atlas of Sox10+ NCPC migration and distribution profile of these cells in adult bladder provided here will serve as a roadmap for future investigation in mouse models of lower urinary tract dysfunction. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. The poster as modernist progenitor

    OpenAIRE

    Katherine Hauser

    2015-01-01

    Ruth E. Iskin’s The Poster: Art, Advertising. Design, and Collecting, 1860s-1900s positions the late-nineteenth-century advertising poster as the progenitor of valued modernist practices typically attached solely to photography and film. Modernist biases separating high art from mass culture account for scholars ignoring posters, however the poster ushered in an innovative reductive graphic style as well as pioneered the notion of multiple originals.

  10. The poster as modernist progenitor

    Directory of Open Access Journals (Sweden)

    Katherine Hauser

    2015-12-01

    Full Text Available Ruth E. Iskin’s The Poster: Art, Advertising. Design, and Collecting, 1860s-1900s positions the late-nineteenth-century advertising poster as the progenitor of valued modernist practices typically attached solely to photography and film. Modernist biases separating high art from mass culture account for scholars ignoring posters, however the poster ushered in an innovative reductive graphic style as well as pioneered the notion of multiple originals.

  11. Gamma-Ray Burst Progenitors

    Science.gov (United States)

    Levan, Andrew; Crowther, Paul; de Grijs, Richard; Langer, Norbert; Xu, Dong; Yoon, Sung-Chul

    2016-12-01

    We review our current understanding of the progenitors of both long and short duration gamma-ray bursts (GRBs). Constraints can be derived from multiple directions, and we use three distinct strands; (i) direct observations of GRBs and their host galaxies, (ii) parameters derived from modelling, both via population synthesis and direct numerical simulation and (iii) our understanding of plausible analog progenitor systems observed in the local Universe. From these joint constraints, we describe the likely routes that can drive massive stars to the creation of long GRBs, and our best estimates of the scenarios that can create compact object binaries which will ultimately form short GRBs, as well as the associated rates of both long and short GRBs. We further discuss how different the progenitors may be in the case of black hole engine or millisecond-magnetar models for the production of GRBs, and how central engines may provide a unifying theme between many classes of extremely luminous transient, from luminous and super-luminous supernovae to long and short GRBs.

  12. Gamma-ray burst progenitors

    CERN Document Server

    Levan, Andrew; de Grijs, Richard; Langer, Norbert; Xu, Dong; Yoon, Sung-Chul

    2016-01-01

    We review our current understanding of the progenitors of both long and short duration gamma-ray bursts (GRBs). Constraints can be derived from multiple directions, and we use three distinct strands; i) direct observations of GRBs and their host galaxies, ii) parameters derived from modeling, both via population synthesis and direct numerical simulation and iii) our understanding of plausible analog progenitor systems observed in the local Universe. From these joint constraints, we describe the likely routes that can drive massive stars to the creation of long GRBs, and our best estimates of the scenarios that can create compact object binaries which will ultimately form short GRBs, as well as the associated rates of both long and short GRBs. We further discuss how different the progenitors may be in the case of black hole engine or millisecond-magnetar models for the production of GRBs, and how central engines may provide a unifying theme between many classes of extremely luminous transient, from luminous an...

  13. Thyroid hormone and retinoic acid interact to regulate zebrafish craniofacial neural crest development.

    Science.gov (United States)

    Bohnsack, Brenda L; Kahana, Alon

    2013-01-15

    Craniofacial and ocular morphogenesis require proper regulation of cranial neural crest migration, proliferation, survival and differentiation. Although alterations in maternal thyroid hormone (TH) are associated with congenital craniofacial anomalies, the role of TH on the neural crest has not been previously described. Using zebrafish, we demonstrate that pharmacologic and genetic alterations in TH signaling disrupt cranial neural crest migration, proliferation, and survival, leading to craniofacial, extraocular muscle, and ocular developmental abnormalities. In the rostral cranial neural crest that gives rise to the periocular mesenchyme and the frontonasal process, retinoic acid (RA) rescued migratory defects induced by decreased TH signaling. In the caudal cranial neural crest, TH and RA had reciprocal effects on anterior and posterior pharyngeal arch development. The interactions between TH and RA signaling were partially mediated by the retinoid X receptor. We conclude that TH regulates both rostral and caudal cranial neural crest. Further, coordinated interactions of TH and RA are required for proper craniofacial and ocular development.

  14. Promoted neuronal differentiation after activation of alpha4/beta2 nicotinic acetylcholine receptors in undifferentiated neural progenitors.

    Directory of Open Access Journals (Sweden)

    Takeshi Takarada

    Full Text Available BACKGROUND: Neural progenitor is a generic term used for undifferentiated cell populations of neural stem, neuronal progenitor and glial progenitor cells with abilities for proliferation and differentiation. We have shown functional expression of ionotropic N-methyl-D-aspartate (NMDA and gamma-aminobutyrate type-A receptors endowed to positively and negatively regulate subsequent neuronal differentiation in undifferentiated neural progenitors, respectively. In this study, we attempted to evaluate the possible functional expression of nicotinic acetylcholine receptor (nAChR by undifferentiated neural progenitors prepared from neocortex of embryonic rodent brains. METHODOLOGY/PRINCIPAL FINDINGS: Reverse transcription polymerase chain reaction analysis revealed mRNA expression of particular nAChR subunits in undifferentiated rat and mouse progenitors prepared before and after the culture with epidermal growth factor under floating conditions. Sustained exposure to nicotine significantly inhibited the formation of neurospheres composed of clustered proliferating cells and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction activity at a concentration range of 1 µM to 1 mM without affecting cell survival. In these rodent progenitors previously exposed to nicotine, marked promotion was invariably seen for subsequent differentiation into cells immunoreactive for a neuronal marker protein following the culture of dispersed cells under adherent conditions. Both effects of nicotine were significantly prevented by the heteromeric α4β2 nAChR subtype antagonists dihydro-β-erythroidine and 4-(5-ethoxy-3-pyridinyl-N-methyl-(3E-3-buten-1-amine, but not by the homomeric α7 nAChR subtype antagonist methyllycaconitine, in murine progenitors. Sustained exposure to nicotine preferentially increased the expression of Math1 among different basic helix-loop-helix proneural genes examined. In undifferentiated progenitors from embryonic mice

  15. CREST maps somatic structural variation in cancer genomes with base-pair resolution.

    Science.gov (United States)

    Wang, Jianmin; Mullighan, Charles G; Easton, John; Roberts, Stefan; Heatley, Sue L; Ma, Jing; Rusch, Michael C; Chen, Ken; Harris, Christopher C; Ding, Li; Holmfeldt, Linda; Payne-Turner, Debbie; Fan, Xian; Wei, Lei; Zhao, David; Obenauer, John C; Naeve, Clayton; Mardis, Elaine R; Wilson, Richard K; Downing, James R; Zhang, Jinghui

    2011-06-12

    We developed 'clipping reveals structure' (CREST), an algorithm that uses next-generation sequencing reads with partial alignments to a reference genome to directly map structural variations at the nucleotide level of resolution. Application of CREST to whole-genome sequencing data from five pediatric T-lineage acute lymphoblastic leukemias (T-ALLs) and a human melanoma cell line, COLO-829, identified 160 somatic structural variations. Experimental validation exceeded 80%, demonstrating that CREST had a high predictive accuracy.

  16. ENDOWMENTS: THEIR PLACE IN THE SYSTEM OF FINANCING OF HIGHER EDUCATION AND EXPERIENCE OF THEIR USE IN RUSSIA AND ABROAD

    Directory of Open Access Journals (Sweden)

    Andrey Leonov

    2012-01-01

    Full Text Available The present paper demonstrates that existing methods of financing of organizations of higher education in Russia cannot be used as a supporting ttool for knowledge production, which leads to decrease in quality of educational services in the field of higher education. Endowments are proposed as a tool of financing. Endowment statistics for Russia and other countries is given. Obstacles that hinder development of endowments in Russia are analyzed.

  17. Hydraulic evaluation of the Crest Wing wave energy converter

    Energy Technology Data Exchange (ETDEWEB)

    Kofoed, J.P.; Antonishen, M.

    2008-09-15

    The Crest Wing Wave Energy Converter is currently being developed by Henning Pilgaard, of WaveEnergyFyn, Denmark. It is meant to act like a carpet on the water, conforming to the shape of each wave and using that movement to generate power. The thought of making a WEC that acts like a carpet on top of the waves is not new; ongoing or past projects such as the Pelamis and Cockerel Raft were designed with this thought in mind. The real difference with the Crest Wing is that it has skirt drafts, that extend down into the water and create suction; this increases the effective mass of the WEC while minimizing the material use. Special attention was given to the design of the first and last floaters as they are meant to act as a smooth transition between wave and machine. Their purpose is to make sure that no air gets under the two middle floaters so that suction is not broken and the device continues to function well. In summary the Crest Wing functions and is able to produce power with a good overall efficiency. The configuration with relative reference PTO (Power Take Off) is superior. It has not been proven that the idea of mounting skirts on the floaters is leading to a better performance. Thus, the study leads to the conclusion that the idea of making a simple hinged raft type device is good, and it is likely that the construction cost for a device of this type can be kept down. However, the study also leaves the chance that some limited draft of skirts in combination with inlet/outlet devices, could prove beneficial. In case of further testing on this device, an effort should be made to design and construct a more easily and accurately controlled PTO model in the test setup. This could greatly improve the quality of the output of such tests. (ln)

  18. Age- and gender-related changes in the cellularity of human bone marrow and the prevalence of osteoblastic progenitors.

    Science.gov (United States)

    Muschler, G F; Nitto, H; Boehm, C A; Easley, K A

    2001-01-01

    Bone marrow harvested by aspiration contains connective tissue progenitor cells which can be induced to express a bone phenotype in vitro. The number of osteoblastic progenitors can be estimated by counting the colony-forming units which express alkaline phosphatase (CFU-APs). This study was undertaken to test the hypothesis that human aging is associated with a significant change in the number or prevalence of osteoblastic progenitors in the bone marrow. Four 2-ml bone marrow aspirates were harvested bilaterally from the anterior iliac crest of 57 patients, 31 men (age 15-83) and 26 women (age 13-79). A mean of 64 million nucleated cells was harvested per aspirate. The mean prevalence of CFU-APs was found to be 55 per million nucleated cells. These data revealed a significant age-related decline in the number of nucleated cells harvested per aspirate for both men and women (P = 0.002). The number of CFU-APs harvested per aspirate also decreased significantly with age for women (P = 0.02), but not for men (P = 0.3). These findings are relevant to the harvest of bone marrow derived connective tissue progenitors for bone grafting and other tissue engineering applications, and may also be relevant to the pathophysiology of age-related bone loss and post-menopausal osteoporosis.

  19. Overbidding and heterogeneous behavior in contest experiments: A comment on the endowment effect

    OpenAIRE

    Subhasish M. Chowdhury; Moffatt, Peter G.

    2015-01-01

    We revisit the meta-analysis of Sheremeta (2013) on overbidding in contest experiments and focus on the effect of endowment on overbidding. Whereas Sheremeta (2013) assumes that there is a monotonic relationship between endowment and overbidding in his meta-analysis, Baik et al. (2014) find an inverted-U shaped relationship in the analysis of a single experiment. We use the same data as in Sheremeta (2013), but employ a different econometric model which leads to support for the inverted-U sha...

  20. The neural crest stem cells: control of neural crest cell fate and plasticity by endothelin-3

    Directory of Open Access Journals (Sweden)

    ELISABETH DUPIN

    2001-12-01

    Full Text Available How the considerable diversity of neural crest (NC-derived cell types arises in the vertebrate embryo has long been a key question in developmental biology. The pluripotency and plasticity of differentiation of the NC cell population has been fully documented and it is well-established that environmental cues play an important role in patterning the NC derivatives throughout the body. Over the past decade, in vivo and in vitro cellular approaches have unravelled the differentiation potentialities of single NC cells and led to the discovery of NC stem cells. Although it is clear that the final fate of individual cells is in agreement with their final position within the embryo, it has to be stressed that the NC cells that reach target sites are pluripotent and further restrictions occur only late in development. It is therefore a heterogenous collection of cells that is submitted to local environmental signals in the various NC-derived structures. Several factors were thus identified which favor the development of subsets of NC-derived cells in vitro. Moreover, the strategy of gene targeting in mouse has led at identifying new molecules able to control one or several aspects of NC cell differentiation in vivo. Endothelin peptides (and endothelin receptors are among those. The conjunction of recent data obtained in mouse and avian embryos and reviewed here contributes to a better understanding of the action of the endothelin signaling pathway in the emergence and stability of NC-derived cell phenotypes.O modo como a diversidade dos tipos celulares derivados da crista neural (CN surge, no embrião de vertebrado, tem sido uma pergunta chave na biologia do desenvolvimento. A pluripotência e a plasticidade na diferenciação da população de células da CN têm sido intensivamente documentadas, ficando deste modo estabelecido que os factores ambientais têm um papel importante na correta diferenciação dos derivados da CN no organismo. Na d

  1. How Tissue Mechanical Properties Affect Enteric Neural Crest Cell Migration.

    Science.gov (United States)

    Chevalier, N R; Gazguez, E; Bidault, L; Guilbert, T; Vias, C; Vian, E; Watanabe, Y; Muller, L; Germain, S; Bondurand, N; Dufour, S; Fleury, V

    2016-02-18

    Neural crest cells (NCCs) are a population of multipotent cells that migrate extensively during vertebrate development. Alterations to neural crest ontogenesis cause several diseases, including cancers and congenital defects, such as Hirschprung disease, which results from incomplete colonization of the colon by enteric NCCs (ENCCs). We investigated the influence of the stiffness and structure of the environment on ENCC migration in vitro and during colonization of the gastrointestinal tract in chicken and mouse embryos. We showed using tensile stretching and atomic force microscopy (AFM) that the mesenchyme of the gut was initially soft but gradually stiffened during the period of ENCC colonization. Second-harmonic generation (SHG) microscopy revealed that this stiffening was associated with a gradual organization and enrichment of collagen fibers in the developing gut. Ex-vivo 2D cell migration assays showed that ENCCs migrated on substrates with very low levels of stiffness. In 3D collagen gels, the speed of the ENCC migratory front decreased with increasing gel stiffness, whereas no correlation was found between porosity and ENCC migration behavior. Metalloprotease inhibition experiments showed that ENCCs actively degraded collagen in order to progress. These results shed light on the role of the mechanical properties of tissues in ENCC migration during development.

  2. Slit molecules prevent entrance of trunk neural crest cells in developing gut.

    Science.gov (United States)

    Zuhdi, Nora; Ortega, Blanca; Giovannone, Dion; Ra, Hannah; Reyes, Michelle; Asención, Viviana; McNicoll, Ian; Ma, Le; de Bellard, Maria Elena

    2015-04-01

    Neural crest cells emerge from the dorsal neural tube early in development and give rise to sensory and sympathetic ganglia, adrenal cells, teeth, melanocytes and especially enteric nervous system. Several inhibitory molecules have been shown to play important roles in neural crest migration, among them are the chemorepulsive Slit1-3. It was known that Slits chemorepellants are expressed at the entry to the gut, and thus could play a role in the differential ability of vagal but not trunk neural crest cells to invade the gut and form enteric ganglia. Especially since trunk neural crest cells express Robo receptor while vagal do not. Thus, although we know that Robo mediates migration along the dorsal pathway in neural crest cells, we do not know if it is responsible in preventing their entry into the gut. The goal of this study was to further corroborate a role for Slit molecules in keeping trunk neural crest cells away from the gut. We observed that when we silenced Robo receptor in trunk neural crest, the sympathoadrenal (somites 18-24) were capable of invading gut mesenchyme in larger proportion than more rostral counterparts. The more rostral trunk neural crest tended not to migrate beyond the ventral aorta, suggesting that there are other repulsive molecules keeping them away from the gut. Interestingly, we also found that when we silenced Robo in sacral neural crest they did not wait for the arrival of vagal crest but entered the gut and migrated rostrally, suggesting that Slit molecules are the ones responsible for keeping them waiting at the hindgut mesenchyme. These combined results confirm that Slit molecules are responsible for keeping the timeliness of colonization of the gut by neural crest cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Zebrafish arl6ip1 is required for neural crest development during embryogenesis.

    Directory of Open Access Journals (Sweden)

    Chi-Tang Tu

    Full Text Available BACKGROUND: Although the embryonic expression pattern of ADP ribosylation factor-like 6 interacting protein 1 (Arl6ip1 has been reported, its function in neural crest development is unclear. METHODS/PRINCIPAL FINDINGS: We found that knockdown of Arl6ip1 caused defective embryonic neural crest derivatives that were particularly severe in craniofacial cartilages. Expressions of the ectodermal patterning factors msxb, dlx3b, and pax3 were normal, but the expressions of the neural crest specifier genes foxd3, snai1b, and sox10 were greatly reduced. These findings suggest that arl6ip1 is essential for specification of neural crest derivatives, but not neural crest induction. Furthermore, we revealed that the streams of crestin- and sox10-expressing neural crest cells, which migrate ventrally from neural tube into trunk, were disrupted in arl6ip1 morphants. This migration defect was not only in the trunk neural crest, but also in the enteric tract where the vagal-derived neural crest cells failed to populate the enteric nervous system. We found that this migration defect was induced by dampened Shh signaling, which may have resulted from defective cilia. These data further suggested that arl6ip1 is required for neural crest migration. Finally, by double-staining of TUNEL and crestin, we confirmed that the loss of neural crest cells could not be attributed to apoptosis. CONCLUSIONS/SIGNIFICANCE: Therefore, we concluded that arl6ip1 is required for neural crest migration and sublineage specification.

  4. Crested wheatgrass (Agropyron cristatum seedings in Western Colorado: What can we learn?

    Directory of Open Access Journals (Sweden)

    James Dollerschell

    2012-12-01

    Full Text Available Non-native species have been widely transported, becoming components of ecosystems worldwide. In some cases this can change thestructure and function of an ecosystem. Crested wheatgrass (Agropyron cristatum, Agropyron spp. was introduced into the Western U.S. inthe late 18th and early 19th centuries. Since introduction, it has been planted in western rangelands currently occupying millions of acres.Crested wheatgrass causes significant changes in areas where it dominates the vegetation, and restoring rangelands planted with crested wheatgrass to higher plant diversity and ecosystem function has been met with limited success. Here we revisit historical frequency monitoring data collected in western Colorado on public lands that were planted with crested wheatgrass between 1940 and 1980. We also monitored vegetation before and after mechanical treatment (removal of vegetation with the use of a dixie harrow pulled behind a tractor and re-seeding of desirable species in three areas dominated by crested wheatgrass. We looked for increasing or decreasing trends in plant species, and for plant species that persist with crested wheatgrass. We found that crested wheatgrass increased significantly (p=0.09 over time, we also found five species of grasses, two shrub species, and one forb species that were persistent in areas planted with crested wheatgrass. We found that in mechanically treated areas, the only significant trend was a reduction of native grasses (p<0.05. Our findings suggest that in areas planted with crested wheatgrass, frequency of crested wheatgrass can increase over time. Further, mechanical treatments coupled with seeding were not effective at reducing crested wheatgrass cover, or at increasing native and desirable species. These sites may have experienced a shift to a stable state.

  5. Mice with DNA repair gene Ercc1 deficiency in a neural crest lineage are a model for late-onset Hirschsprung disease.

    Science.gov (United States)

    Selfridge, Jim; Song, Liang; Brownstein, David G; Melton, David W

    2010-06-04

    The Ercc1 gene is essential for nucleotide excision repair and is also important in recombination repair and the repair of interstrand crosslinks. We have previously used a floxed Ercc1 allele with a keratinocyte-specific Cre recombinase transgene to inactivate Ercc1 in the epidermal layer of the skin and so generate a mouse model for UV-induced non-melanoma skin cancer. Now, in an attempt to generate a model for UV-induced melanoma, we have used the floxed Ercc1 allele in combination with a Cre transgene under the control of the tyrosinase gene promoter to produce mice with Ercc1-deficient melanocytes that are hypersensitive to UV irradiation. These animals developed normally, but died when 4-6 months old with severe colonic obstruction. Melanocytes are derived from the neural crest and the tyrosinase promoter is also expressed in additional neural crest-derived lineages, including the progenitors of the parasympathetic nervous system that innervates the gastrointestinal tract and controls gut peristalsis. A functional enteric nervous system developed in floxed Ercc1 mice with the tyrosinase Cre transgene, but was found to have degenerated in the colons of affected mice. We suggest that accumulating unrepaired endogenous DNA damage in the Ercc1-deficient colonic parasympathetic ganglia leads to the degeneration of this network and results in a colonic obstructive disorder that resembles late-onset Hirschsprung disease in man.

  6. Neurodevelopment. Parasympathetic neurons originate from nerve-associated peripheral glial progenitors.

    Science.gov (United States)

    Dyachuk, Vyacheslav; Furlan, Alessandro; Shahidi, Maryam Khatibi; Giovenco, Marcela; Kaukua, Nina; Konstantinidou, Chrysoula; Pachnis, Vassilis; Memic, Fatima; Marklund, Ulrika; Müller, Thomas; Birchmeier, Carmen; Fried, Kaj; Ernfors, Patrik; Adameyko, Igor

    2014-07-04

    The peripheral autonomic nervous system reaches far throughout the body and includes neurons of diverse functions, such as sympathetic and parasympathetic. We show that the parasympathetic system in mice--including trunk ganglia and the cranial ciliary, pterygopalatine, lingual, submandibular, and otic ganglia--arise from glial cells in nerves, not neural crest cells. The parasympathetic fate is induced in nerve-associated Schwann cell precursors at distal peripheral sites. We used multicolor Cre-reporter lineage tracing to show that most of these neurons arise from bi-potent progenitors that generate both glia and neurons. This nerve origin places cellular elements for generating parasympathetic neurons in diverse tissues and organs, which may enable wiring of the developing parasympathetic nervous system.

  7. Cost vs. Market Value: The Case for Reporting Endowment Investments at Market Value.

    Science.gov (United States)

    Bland, Harold

    1992-01-01

    The difference between cost and market value of endowment investments is significant for many colleges and universities. These investments should always be reported at market value to provide relevant, comparable, consistent, and understandable financial information. Nonmanagement users of institutional financial statements prefer market rather…

  8. A Bull Market Gave Colleges 18% Return on Endowments in 1998.

    Science.gov (United States)

    van der Werf, Martin

    1999-01-01

    A national survey of 346 private and 162 public colleges found that the number of institution with billion-dollar endowments grew from 25 to 31, and that all responding institutions had at least some return on investments, ranging from 3.7% to 38% The greatest change was an increase in the amount of money invested in hedge funds. (MSE)

  9. 76 FR 16842 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-03-25

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... one meeting of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy...): Arts Education (application review): April 14, 2011, by teleconference. This meeting, from 1 p.m. to...

  10. 76 FR 20719 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-04-13

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... nine meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... recommendations on financial assistance under the National Foundation on the Arts and the Humanities Act of...

  11. 76 FR 81542 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-12-28

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... meeting of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy Hanks...): Media Arts (application review): January 24-26, 2012 in Room 716. A portion of this meeting, from 3...

  12. 75 FR 63516 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-10-15

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... twelve meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy.... each day, will be closed. Arts Education (application review): November 1-5, 2010 in Room 716....

  13. 75 FR 32817 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-06-09

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... eight meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... a.m. to 3:30 p.m. on July 16th, will be closed. Visual Arts (application review): July 13-16,...

  14. 76 FR 59447 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-09-26

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... two meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy...): Arts Education (application review): October 24-26, 2011 in Room 627. This meeting, from 9 a.m. to 6...

  15. 75 FR 26284 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-05-11

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... nine meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy...:30 p.m. EDT, will be closed. Folk and Traditional Arts (application review): June 3-4, 2010 in...

  16. 75 FR 41902 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-07-19

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... three meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... assistance under the National Foundation on the Arts and the Humanities Act of 1965, as amended,...

  17. 76 FR 41308 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-07-13

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... two meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... financial assistance under the National Foundation on the Arts and the Humanities Act of 1965, as...

  18. 75 FR 35845 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-06-23

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... three meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... National Foundation on the Arts and the Humanities Act of 1965, as amended, including information given...

  19. 76 FR 28244 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-05-16

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... one meeting of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy..., evaluation, and recommendations on financial assistance under the National Foundation on the Arts and...

  20. 75 FR 44815 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-07-29

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... one meeting of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy..., discussion, evaluation, and recommendations on financial assistance under the National Foundation on the...

  1. 76 FR 28101 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-05-13

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... eleven meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate): Folk and Traditional Arts (application review): June 1-2, 2011 in Room 716. This meeting, from...

  2. 76 FR 35049 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-06-15

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... eleven meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate). All meetings will be closed. Visual Arts (application review): July 6-8, 2011 in Room...

  3. 75 FR 11940 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-03-12

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to section 10(a... meeting of the Arts Advisory Committee will be held by teleconference from 1 p.m. to 1:20 p.m. (ending..., discussion, evaluation, and recommendations on financial assistance under the National Foundation on the...

  4. 76 FR 13240 - National Endowment for the Arts; National Council on the Arts 172nd Meeting

    Science.gov (United States)

    2011-03-10

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; National Council on the Arts 172nd Meeting... hereby given that a meeting of the National Council on the Arts will be held on March 24-25 2011 in Rooms... meeting will begin with opening remarks by the Chairman, followed by presentations on Arts...

  5. 75 FR 69474 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-11-12

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... eleven meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate): Visual Arts (application review): November 30-December 2, 2010 in Room 716. This meeting, from...

  6. 76 FR 78316 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-12-16

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... eleven meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate): Media Arts (application review): January 10-12, 2012 in Room 627. This meeting, from 9 a.m. to...

  7. 75 FR 2163 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-01-14

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... eight meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... the National Foundation on the Arts and the Humanities Act of 1965, as amended, including...

  8. 75 FR 77674 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-12-13

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... nine meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate): State and Regional/Arts Education (review of State Arts Agency Partnership Agreements):...

  9. 76 FR 70510 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2011-11-14

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a... ten meetings of the Arts Advisory Panel to the National Council on the Arts will be held at the Nancy... approximate): Arts Education (application review): November 29-December 2, 2011 in Room 714. This...

  10. 75 FR 19664 - National Endowment for the Arts; Arts Advisory Panel

    Science.gov (United States)

    2010-04-15

    ...] [FR Doc No: 2010-8613] NATIONAL FOUNDATION ON THE ARTS AND THE HUMANITIES National Endowment for the Arts; Arts Advisory Panel Pursuant to Section 10(a)(2) of the Federal Advisory Committee Act (Pub. L. 92-463), as amended, notice is hereby given that four meetings of the Arts Advisory Panel to...

  11. NMR study of 1,4-dihydropyridine derivatives endowed with long alkyl and functionalized chains

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, Margarita; Salfran, Esperanza; Rodriguez, Hortensia; Coro, Julieta, E-mail: msuarez@fq.uh.c [Universidad de La Habana (Cuba). Facultad de Quimica. Lab. de Sintesis Organica; Molero, Dolores; Saez, Elena [Universidad Complutense, Madrid (Spain). CAI-RMN; Martinez-Alvarez, Roberto; Martin, Nazario [Universidad Complutense, Madrid (Spain). Facultad de Quimica. Dept. de Quimica Organica I

    2011-07-01

    The {sup 1}H , {sup 13}C and {sup 15}N NMR spectroscopic data for 1,4-dihydropyridine endowed with long alkyl and functionalized chain on C-3 and C-5, have been fully assigned by combination of one- and two dimensional experiments (DEPT, HMBC, HMQC, COSY, nOe). (author)

  12. 45 CFR 1159.13 - In what other situations will the Endowment disclose its records?

    Science.gov (United States)

    2010-10-01

    ... regulations published at 45 CFR part 1100; (3) For a routine use as published in the annual notice in the... disclose its records? 1159.13 Section 1159.13 Public Welfare Regulations Relating to Public Welfare... OF THE PRIVACY ACT OF 1974 § 1159.13 In what other situations will the Endowment disclose its...

  13. The Endowed Schools Act, 1869 -- A Middle-Class Conspiracy? The South-West Lancashire Evidence

    Science.gov (United States)

    Gomez, F. G.

    1974-01-01

    The exclusion of poor scholars from the grammar schools of South-West Lancashire resulted from the economic and social conditions of mid-nineteenth century England rather than to the passage of the Endowed Schools Act in 1869. (Author/WM)

  14. 34 CFR 628.5 - What regulations apply to the Endowment Challenge Grant Program?

    Science.gov (United States)

    2010-07-01

    ... Program? 628.5 Section 628.5 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION ENDOWMENT CHALLENGE GRANT PROGRAM....217. (iv) 34 CFR part 79 (Intergovernmental Review of Department of Education Programs and...

  15. Autonomy or Oligarchy? The Changing Effects of University Endowments in Winner-Take-All Markets

    Science.gov (United States)

    Meyer, Heinz-Dieter; Zhou, Kai

    2017-01-01

    This paper directs attention to important changes in the role and funding of elite private universities in the USA. At the center of these changes is the private endowment--an institution that has for much of its history been a pivotal element of innovation and autonomy, but which is recently tilting towards the production and reproduction of…

  16. Marketing Strategies for a Low Endowment Private University in the 1990's.

    Science.gov (United States)

    Wallingford, Harlan P.; Berger, Karen

    1993-01-01

    It is suggested that low-endowment private universities must apply better marketing techniques in strategic planning to ensure survival. Recommendations are made for using market research effectively, identifying new markets, and directing media communication accurately. The student's role as consumer is seen as the starting point for product and…

  17. 45 CFR 1150.23 - How will the Endowment coordinate salary offsets with other agencies?

    Science.gov (United States)

    2010-10-01

    ... (Continued) NATIONAL FOUNDATION ON THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE ARTS COLLECTION OF... entitled to payments from the Civil Service Retirement and Disability Fund or other similar payments that... prohibited, that money due and payable to the employee from the Civil Service Retirement and Disability...

  18. Lineage tracing of neuromesodermal progenitors reveals novel Wnt-dependent roles in trunk progenitor cell maintenance and differentiation

    National Research Council Canada - National Science Library

    Garriock, Robert J; Chalamalasetty, Ravindra B; Kennedy, Mark W; Canizales, Lauren C; Lewandoski, Mark; Yamaguchi, Terry P

    2015-01-01

    ...) of the trunk region while suppressing neural specification. Recent lineage-tracing experiments have demonstrated that these trunk neural progenitors and PMPs derive from a common multipotent progenitor called the neuromesodermal progenitor (NMP...

  19. Pax3 and Zic1 trigger the early neural crest gene regulatory network by the direct activation of multiple key neural crest specifiers.

    Science.gov (United States)

    Plouhinec, Jean-Louis; Roche, Daniel D; Pegoraro, Caterina; Figueiredo, Ana Leonor; Maczkowiak, Frédérique; Brunet, Lisa J; Milet, Cécile; Vert, Jean-Philippe; Pollet, Nicolas; Harland, Richard M; Monsoro-Burq, Anne H

    2014-02-15

    Neural crest development is orchestrated by a complex and still poorly understood gene regulatory network. Premigratory neural crest is induced at the lateral border of the neural plate by the combined action of signaling molecules and transcription factors such as AP2, Gbx2, Pax3 and Zic1. Among them, Pax3 and Zic1 are both necessary and sufficient to trigger a complete neural crest developmental program. However, their gene targets in the neural crest regulatory network remain unknown. Here, through a transcriptome analysis of frog microdissected neural border, we identified an extended gene signature for the premigratory neural crest, and we defined novel potential members of the regulatory network. This signature includes 34 novel genes, as well as 44 known genes expressed at the neural border. Using another microarray analysis which combined Pax3 and Zic1 gain-of-function and protein translation blockade, we uncovered 25 Pax3 and Zic1 direct targets within this signature. We demonstrated that the neural border specifiers Pax3 and Zic1 are direct upstream regulators of neural crest specifiers Snail1/2, Foxd3, Twist1, and Tfap2b. In addition, they may modulate the transcriptional output of multiple signaling pathways involved in neural crest development (Wnt, Retinoic Acid) through the induction of key pathway regulators (Axin2 and Cyp26c1). We also found that Pax3 could maintain its own expression through a positive autoregulatory feedback loop. These hierarchical inductions, feedback loops, and pathway modulations provide novel tools to understand the neural crest induction network.

  20. 76 FR 15971 - Eagle Mountain Pumped Storage Hydroelectric Project; Eagle Crest Energy; Notice of Teleconference

    Science.gov (United States)

    2011-03-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project; Eagle Crest Energy... Eagle Crest Energy as part of its on-going Section 7 Endangered Species Act consultation efforts. e....

  1. 76 FR 22699 - Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy; Notice of Teleconference

    Science.gov (United States)

    2011-04-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy... Eagle Crest Energy as part of its on-going Section 7 Endangered Species Act consultation efforts. e....

  2. Analysis of neural crest-derived clones reveals novel aspects of facial development

    NARCIS (Netherlands)

    Kaucka, Marketa; Ivashkin, Evgeny; Gyllborg, Daniel; Zikmund, Tomas; Tesarova, Marketa; Kaiser, Jozef; Xie, Meng; Petersen, Julian; Pachnis, Vassilis; Nicolis, Silvia K; Yu, Tian; Sharpe, Paul; Arenas, Ernest; Brismar, Hjalmar; Blom, Hans; Clevers, Hans; Suter, Ueli; Chagin, Andrei S; Fried, Kaj; Hellander, Andreas; Adameyko, Igor

    2016-01-01

    Cranial neural crest cells populate the future facial region and produce ectomesenchyme-derived tissues, such as cartilage, bone, dermis, smooth muscle, adipocytes, and many others. However, the contribution of individual neural crest cells to certain facial locations and the general spatial clonal

  3. 75 FR 3217 - Eagle Crest Energy Company; Notice of Application Ready for Environmental Analysis and Soliciting...

    Science.gov (United States)

    2010-01-20

    ... Energy Regulatory Commission Eagle Crest Energy Company; Notice of Application Ready for Environmental... filed: June 23, 2009. d. Applicant: Eagle Crest Energy Company. e. Name of Project: Eagle Mountain... Eagle Mountain Mine in Riverside County, California, near the Town of Desert Center, California,...

  4. 27 CFR 70.164 - Surrender of property subject to levy in the case of life insurance and endowment contracts.

    Science.gov (United States)

    2010-04-01

    ... subject to levy in the case of life insurance and endowment contracts. 70.164 Section 70.164 Alcohol... the case of life insurance and endowment contracts. (a) In general. This section provides special rules relating to the surrender of property subject to levy in the case of life insurance and...

  5. 26 CFR 1.61-10 - Alimony and separate maintenance payments; annuities; income from life insurance and endowment...

    Science.gov (United States)

    2010-04-01

    ...; annuities; income from life insurance and endowment contracts. 1.61-10 Section 1.61-10 Internal Revenue... separate maintenance payments; annuities; income from life insurance and endowment contracts. (a) In general. Alimony and separate maintenance payments, annuities, and income from life insurance...

  6. 45 CFR 1159.5 - What government entities will the Endowment notify of proposed changes to its systems of records?

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false What government entities will the Endowment notify of proposed changes to its systems of records? 1159.5 Section 1159.5 Public Welfare Regulations... ENDOWMENT FOR THE ARTS IMPLEMENTATION OF THE PRIVACY ACT OF 1974 § 1159.5 What government entities will...

  7. Defective ALK5 signaling in the neural crest leads to increased postmigratory neural crest cell apoptosis and severe outflow tract defects

    Directory of Open Access Journals (Sweden)

    Sucov Henry M

    2006-11-01

    Full Text Available Abstract Background Congenital cardiovascular diseases are the most common form of birth defects in humans. A substantial portion of these defects has been associated with inappropriate induction, migration, differentiation and patterning of pluripotent cardiac neural crest stem cells. While TGF-β-superfamily signaling has been strongly implicated in neural crest cell development, the detailed molecular signaling mechanisms in vivo are still poorly understood. Results We deleted the TGF-β type I receptor Alk5 specifically in the mouse neural crest cell lineage. Failure in signaling via ALK5 leads to severe cardiovascular and pharyngeal defects, including inappropriate remodeling of pharyngeal arch arteries, abnormal aortic sac development, failure in pharyngeal organ migration and persistent truncus arteriosus. While ALK5 is not required for neural crest cell migration, our results demonstrate that it plays an important role in the survival of post-migratory cardiac neural crest cells. Conclusion Our results demonstrate that ALK5-mediated signaling in neural crest cells plays an essential cell-autonomous role in the pharyngeal and cardiac outflow tract development.

  8. Dual function of Slit2 in repulsion and enhanced migration of trunk, but not vagal, neural crest cells.

    Science.gov (United States)

    De Bellard, Maria Elena; Rao, Yi; Bronner-Fraser, Marianne

    2003-07-21

    Neural crest precursors to the autonomic nervous system form different derivatives depending upon their axial level of origin; for example, vagal, but not trunk, neural crest cells form the enteric ganglia of the gut. Here, we show that Slit2 is expressed at the entrance of the gut, which is selectively invaded by vagal, but not trunk, neural crest. Accordingly, only trunk neural crest cells express Robo receptors. In vivo and in vitro experiments demonstrate that trunk, not vagal, crest cells avoid cells or cell membranes expressing Slit2, thereby contributing to the differential ability of neural crest populations to invade and innervate the gut. Conversely, exposure to soluble Slit2 significantly increases the distance traversed by trunk neural crest cells. These results suggest that Slit2 can act bifunctionally, both repulsing and stimulating the motility of trunk neural crest cells.

  9. Medical image of the week: CREST plus ILD

    Directory of Open Access Journals (Sweden)

    Oliva I

    2013-06-01

    Full Text Available A 60 year old female with a history of fibromyalgia presented with dyspnea and skin changes, predominantly on the hands. Physical exam and imaging showed classic findings of limited cutaneous systemic sclerosis (scleroderma CREST syndrome. Calcinosis cutis (Figure 1A, Raynaud’s (not shown but endorsed by the patient, Esophageal dysmotility (Figure 1B, dilated esophagus, Sclerodactyly (Figure 1C, and Teleganectasias (Figure 1D were all present. Ground glass opacities were seen predominantly in the bilateral lower lung zones, associated with increased reticular markings (Figure 2A, and traction bronchiectasis (Figure 2B. Pulmonary involvement is noted in the majority of scleroderma patients. Interstitial lung disease (ILD is common and often portends a poor prognosis.

  10. CREST: Center for Renewable Energy Science and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Billo, Richard E. [Univ. of Texas, Arlington, TX (United States); Rajeshwar, Krishnan [Univ. of Texas, Arlington, TX (United States)

    2012-03-20

    The DOE project addressed an approach to the hydrogen economy by researching hydrogen generation from low cost domestic fossil fuel sources. Specifically, the CREST research team developed new processes for extracting hydrogen from southwestern lignite for the production of clean synthetic fuels such as synthetic crude oil that is free of sulfur, carbon dioxide and other pollutants that can be shipped to nearby Texas refineries and power plants for development of transportation fuels and power generation. Research was also undertaken to convert any potential by-products of this process such as CO2 to useful chemicals and gases which may be recycled and used as feedstock to the synthetic fuel process. Finally, to ensure the proposed process is functional beyond bench scale, a detailed design of a pilot plant was completed. The overall project was divided into five tasks including a management task as outlined below.

  11. Neural Crest As the Source of Adult Stem Cells

    Science.gov (United States)

    Pierret, Chris; Spears, Kathleen; Maruniak, Joel A.; Kirk, Mark D.

    2012-01-01

    Recent studies suggest that adult stem cells can cross germ layer boundaries. For example, bone marrow-derived stem cells appear to differentiate into neurons and glial cells, as well as other types of cells. How can stem cells from bone marrow, pancreas, skin, or fat become neurons and glia; in other words, what molecular and cellular events direct mesodermal cells to a neural fate? Transdifferentiation, dediffereniation, and fusion of donor adult stem cells with fully differentiated host cells have been proposed to explain the plasticity of adult stem cells. Here we review the origin of select adult stem cell populations and propose a unifying hypothesis to explain adult stem cell plasticity. In addition, we outline specific experiments to test our hypothesis. We propose that peripheral, tissue-derived, or adult stem cells are all progeny of the neural crest. PMID:16646675

  12. Environmental Design Guidelines for Low Crested Coastal Structures

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Hawkins, Stephen J.; Zanuttigh, Barbara

    changes and beach value, which clearly exists based on EC research experiences and particularly on results obtained by DELOS Project (www.delos.unibo.it) for Low Crested Structures (LCSs), suggests the necessity of integrated approaches and thus the relevance of design guidelines covering: structure...... (Chapters 1-10) contains the description of the design methodology, from the preliminary identification of design alternatives till the selection of the sustainable scheme and its construction. The second part presents: the analysis of the performance of beach defences in DELOS study sites, which were...... methodological tools both for the engineering design of structures and for prediction of performance and environmental impacts of such structures. It is anticipated that the guidelines will provide valuable inputs to coastal zone management plans. The target audience for this set of guidelines is consulting...

  13. Interface dynamos in supernova progenitors

    CERN Document Server

    Blackman, E G; Thomas, J H; Blackman, Eric G.; Nordhaus, Jason T.; Thomas, John H.

    2004-01-01

    Observational evidence for anisotropy in supernovae (SN) and their phenomenological connection to jetted sources such as gamma-ray bursts^Mhave revived considerations of the role magnetohydrodynamic outflows might play therein. Understanding the types of dynamos that might operate in supernova progenitors is therefore relevant. In contrast to previous work, here we study an ``interface dynamo'' for the conditions of a rapidly rotating neutron star surrounded by a convective envelope. Such dynamos have been studied for the Sun, naked white dwarfs,and post-AGB stars, where analogous configurations of strong shear layers surrounded by convective envelopes are present. The interface dynamo provides estimates of large-scale poloidal and toroidal fields, whose product enters the Poynting flux. Because the poloidal field is much weaker than the toroidal magnetic field, the actual average Poynting flux is lower than rough estimates which invoke the only the magnitude of the total magnetic energy. The lower value is s...

  14. Progenitors of Supernovae Type Ia

    CERN Document Server

    Toonen, S; Bours, M; Zwart, S Portegies; Claeys, J; Mennekens, N; Ruiter, A

    2013-01-01

    Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. The standard scenarios involve thermonuclear explosions of carbon/oxygen white dwarfs approaching the Chandrasekhar mass; either by accretion from a companion or by a merger of two white dwarfs. We investigate the contribution from both channels to the SNIa rate with the binary population synthesis (BPS) code SeBa in order to constrain binary processes such as the mass retention efficiency of WD accretion and common envelope evolution. We determine the theoretical rates and delay time distribution of SNIa progenitors and in particular study how assumptions affect the predicted rates.

  15. File list: Unc.PSC.05.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.PSC.05.AllAg.hESC_derived_neural_crests hg19 Unclassified Pluripotent stem cell hESC derived neural cres...ts SRX059366 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.PSC.05.AllAg.hESC_derived_neural_crests.bed ...

  16. File list: InP.PSC.05.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.PSC.05.AllAg.hESC_derived_neural_crests hg19 Input control Pluripotent stem cel...l hESC derived neural crests SRX1091573,SRX059369,SRX059361 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.PSC.05.AllAg.hESC_derived_neural_crests.bed ...

  17. File list: Pol.PSC.10.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.10.AllAg.hESC_derived_neural_crests hg19 RNA polymerase Pluripotent stem ce...ll hESC derived neural crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.PSC.10.AllAg.hESC_derived_neural_crests.bed ...

  18. File list: NoD.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.PSC.20.AllAg.hESC_derived_neural_crests hg19 No description Pluripotent stem ce...ll hESC derived neural crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/NoD.PSC.20.AllAg.hESC_derived_neural_crests.bed ...

  19. File list: Pol.PSC.50.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.50.AllAg.hESC_derived_neural_crests hg19 RNA polymerase Pluripotent stem ce...ll hESC derived neural crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.PSC.50.AllAg.hESC_derived_neural_crests.bed ...

  20. File list: NoD.PSC.50.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.PSC.50.AllAg.hESC_derived_neural_crests hg19 No description Pluripotent stem ce...ll hESC derived neural crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/NoD.PSC.50.AllAg.hESC_derived_neural_crests.bed ...

  1. File list: Pol.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.20.AllAg.hESC_derived_neural_crests hg19 RNA polymerase Pluripotent stem ce...ll hESC derived neural crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.PSC.20.AllAg.hESC_derived_neural_crests.bed ...

  2. File list: InP.PSC.10.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.PSC.10.AllAg.hESC_derived_neural_crests hg19 Input control Pluripotent stem cel...l hESC derived neural crests SRX1091573,SRX059369,SRX059361 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.PSC.10.AllAg.hESC_derived_neural_crests.bed ...

  3. File list: NoD.PSC.05.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.PSC.05.AllAg.hESC_derived_neural_crests hg19 No description Pluripotent stem ce...ll hESC derived neural crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/NoD.PSC.05.AllAg.hESC_derived_neural_crests.bed ...

  4. File list: Pol.PSC.05.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.05.AllAg.hESC_derived_neural_crests hg19 RNA polymerase Pluripotent stem cell hESC derived neural... crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.PSC.05.AllAg.hESC_derived_neural_crests.bed ...

  5. File list: InP.PSC.50.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.PSC.50.AllAg.hESC_derived_neural_crests hg19 Input control Pluripotent stem cell hESC derived neural... crests SRX1091573,SRX059369,SRX059361 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.PSC.50.AllAg.hESC_derived_neural_crests.bed ...

  6. File list: Unc.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.PSC.20.AllAg.hESC_derived_neural_crests hg19 Unclassified Pluripotent stem cell hESC derived neural... crests SRX059366 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.PSC.20.AllAg.hESC_derived_neural_crests.bed ...

  7. File list: NoD.PSC.10.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.PSC.10.AllAg.hESC_derived_neural_crests hg19 No description Pluripotent stem cell hESC derived neural... crests http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/NoD.PSC.10.AllAg.hESC_derived_neural_crests.bed ...

  8. File list: Unc.PSC.50.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.PSC.50.AllAg.hESC_derived_neural_crests hg19 Unclassified Pluripotent stem cell hESC derived neural... crests SRX059366 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.PSC.50.AllAg.hESC_derived_neural_crests.bed ...

  9. File list: InP.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.PSC.20.AllAg.hESC_derived_neural_crests hg19 Input control Pluripotent stem cell hESC derived neural... crests SRX1091573,SRX059369,SRX059361 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.PSC.20.AllAg.hESC_derived_neural_crests.bed ...

  10. 76 FR 5580 - Eagle Crest Energy Company; Notice of Applicant-Proposed Water Pipeline Route for the Proposed...

    Science.gov (United States)

    2011-02-01

    ... Energy Regulatory Commission Eagle Crest Energy Company; Notice of Applicant-Proposed Water Pipeline Route for the Proposed Eagle Mountain Pumped Storage Hydroelectric Project and Notice of Public Meetings January 21, 2011. On June 22, 2009, Eagle Crest Energy Company (Eagle Crest or applicant) filed...

  11. Divergent roles for Eph and Ephrin in Avian Cranial Neural Crest

    Directory of Open Access Journals (Sweden)

    Burke Robert D

    2008-05-01

    Full Text Available Abstract Background As in other vertebrates, avian hindbrain neural crest migrates in streams to specific branchial arches. Signalling from Eph receptors and ephrins has been proposed to provide a molecular mechanism that guides the cells restricting them to streams. In mice and frogs, cranial neural crest express a combination of Eph receptors and ephrins that appear to exclude cells from adjacent tissues by forward and reverse signalling. The objective of this study was to provide comparative data on the distribution and function of Eph receptors and ephrins in avian embryos. Results To distinguish neural crest from bordering ectoderm and head mesenchyme, we have co-labelled embryos for Eph or ephrin RNA and a neural crest marker protein. Throughout their migration avian cranial neural crest cells express EphA3, EphA4, EphA7, EphB1, and EphB3 and move along pathways bordered by non-neural crest cells expressing ephrin-B1. In addition, avian cranial neural crest cells express ephrin-B2 and migrate along pathways bordered by non-neural crest cells expressing EphB2. Thus, the distribution of avian Eph receptors and ephrins differs from those reported in other vertebrates. In stripe assays when explanted cranial neural crest were given the choice between FN or FN plus clustered ephrin-B1 or EphB2 fusion protein, the cells strongly localize to lanes containing only FN. This preference is mitigated in the presence of soluble ephrin-B1 or EphB2 fusion protein. Conclusion These findings show that avian cranial neural crest use Eph and ephrin receptors as other vertebrates in guiding migration. However, the Eph receptors are expressed in different combinations by neural crest destined for each branchial arch and ephrin-B1 and ephrin-B2 appear to have opposite roles to those reported to guide cranial neural crest migration in mice. Unlike many of the signalling, specification, and effector pathways of neural crest, the roles of Eph receptors and ephrins

  12. ALK5-mediated transforming growth factor β signaling in neural crest cells controls craniofacial muscle development via tissue-tissue interactions.

    Science.gov (United States)

    Han, Arum; Zhao, Hu; Li, Jingyuan; Pelikan, Richard; Chai, Yang

    2014-08-01

    The development of the craniofacial muscles requires reciprocal interactions with surrounding craniofacial tissues that originate from cranial neural crest cells (CNCCs). However, the molecular mechanism involved in the tissue-tissue interactions between CNCCs and muscle progenitors during craniofacial muscle development is largely unknown. In the current study, we address how CNCCs regulate the development of the tongue and other craniofacial muscles using Wnt1-Cre; Alk5(fl/fl) mice, in which loss of Alk5 in CNCCs results in severely disrupted muscle formation. We found that Bmp4 is responsible for reduced proliferation of the myogenic progenitor cells in Wnt1-Cre; Alk5(fl/fl) mice during early myogenesis. In addition, Fgf4 and Fgf6 ligands were reduced in Wnt1-Cre; Alk5(fl/fl) mice and are critical for differentiation of the myogenic cells. Addition of Bmp4 or Fgf ligands rescues the proliferation and differentiation defects in the craniofacial muscles of Alk5 mutant mice in vitro. Taken together, our results indicate that CNCCs play critical roles in controlling craniofacial myogenic proliferation and differentiation through tissue-tissue interactions. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  13. Phosphotyrosine phosphatase inhibitor bisperoxovanadium endows myogenic cells with enhanced muscle stem cell functions via epigenetic modulation of Sca-1 and Pw1 promoters.

    Science.gov (United States)

    Smeriglio, Piera; Alonso-Martin, Sonia; Masciarelli, Silvia; Madaro, Luca; Iosue, Ilaria; Marrocco, Valeria; Relaix, Frédéric; Fazi, Francesco; Marazzi, Giovanna; Sassoon, David A; Bouché, Marina

    2016-04-01

    Understanding the regulation of the stem cell fate is fundamental for designing novel regenerative medicine strategies. Previous studies have suggested that pharmacological treatments with small molecules provide a robust and reversible regulation of the stem cell program. Previously, we showed that treatment with a vanadium compound influences muscle cell fatein vitro In this study, we demonstrate that treatment with the phosphotyrosine phosphatase inhibitor bisperoxovanadium (BpV) drives primary muscle cells to a poised stem cell stage, with enhanced function in muscle regenerationin vivofollowing transplantation into injured muscles. Importantly, BpV-treated cells displayed increased self-renewal potentialin vivoand replenished the niche in both satellite and interstitial cell compartments. Moreover, we found that BpV treatment induces specific activating chromatin modifications at the promoter regions of genes associated with stem cell fate, includingSca-1andPw1 Thus, our findings indicate that BpV resets the cell fate program by specific epigenetic regulations, such that the committed myogenic cell fate is redirected to an earlier progenitor cell fate stage, which leads to an enhanced regenerative stem cell potential.-Smeriglio, P., Alonso-Martin, S., Masciarelli, S., Madaro, L., Iosue, I., Marrocco, V., Relaix, F., Fazi, F., Marazzi, G., Sassoon, D. A., Bouché, M. Phosphotyrosine phosphatase inhibitor bisperoxovanadium endows myogenic cells with enhanced muscle stem cell functionsviaepigenetic modulation of Sca-1 and Pw1 promoters.

  14. Amphioxus and lamprey AP-2 genes: implications for neural crest evolution and migration patterns

    Science.gov (United States)

    Meulemans, Daniel; Bronner-Fraser, Marianne

    2002-01-01

    The neural crest is a uniquely vertebrate cell type present in the most basal vertebrates, but not in cephalochordates. We have studied differences in regulation of the neural crest marker AP-2 across two evolutionary transitions: invertebrate to vertebrate, and agnathan to gnathostome. Isolation and comparison of amphioxus, lamprey and axolotl AP-2 reveals its extensive expansion in the vertebrate dorsal neural tube and pharyngeal arches, implying co-option of AP-2 genes by neural crest cells early in vertebrate evolution. Expression in non-neural ectoderm is a conserved feature in amphioxus and vertebrates, suggesting an ancient role for AP-2 genes in this tissue. There is also common expression in subsets of ventrolateral neurons in the anterior neural tube, consistent with a primitive role in brain development. Comparison of AP-2 expression in axolotl and lamprey suggests an elaboration of cranial neural crest patterning in gnathostomes. However, migration of AP-2-expressing neural crest cells medial to the pharyngeal arch mesoderm appears to be a primitive feature retained in all vertebrates. Because AP-2 has essential roles in cranial neural crest differentiation and proliferation, the co-option of AP-2 by neural crest cells in the vertebrate lineage was a potentially crucial event in vertebrate evolution.

  15. Comparison between implants inserted into piezo split and unsplit alveolar crests.

    Science.gov (United States)

    Danza, Matteo; Guidi, Riccardo; Carinci, Francesco

    2009-11-01

    Piezoelectric surgery (PES) uses a modulated ultrasonic frequency that permits highly precise and safe hard tissue cutting. A retrospective study on a series of spiral family implants inserted with or without PES split crest was performed to verify if implants inserted into crests split using PES have a comparable outcome to those inserted into unsplit bone. In the period from May 2004 to November 2007, 86 patients (55 women and 31 men, median age 53 yrs) were operated on and 234 spiral family implants were inserted. Among these, 21 were inserted into PES split crest. Mean follow-up was 13 months (3 to 35 months). The Kaplan-Meier algorithm was used to compare the 2 groups in survival and clinical success (ie, decreased bone resorption around implant neck). Only 9 of 234 implants were lost (ie, survival rate 96.2%), all of which belonged to the unsplit group but no statistical difference was demonstrated. To detect if PES split crest produces a better clinical outcome in comparison with fixtures inserted into unsplit alveolar ridges, crestal bone loss was compared in the remaining loaded implants (234--9 lost--5 not prosthetized = 220). No statistical significant difference was detected by comparing implants inserted into PES split crests with untreated alveolar ridges, although a better trend was visible for fixtures inserted into PES split crests. PES split crests provide several advantages and clinical outcomes that are not worse in terms of bone remodeling, if compared with standard procedures.

  16. Review: the role of neural crest cells in the endocrine system.

    Science.gov (United States)

    Adams, Meghan Sara; Bronner-Fraser, Marianne

    2009-01-01

    The neural crest is a pluripotent population of cells that arises at the junction of the neural tube and the dorsal ectoderm. These highly migratory cells form diverse derivatives including neurons and glia of the sensory, sympathetic, and enteric nervous systems, melanocytes, and the bones, cartilage, and connective tissues of the face. The neural crest has long been associated with the endocrine system, although not always correctly. According to current understanding, neural crest cells give rise to the chromaffin cells of the adrenal medulla, chief cells of the extra-adrenal paraganglia, and thyroid C cells. The endocrine tumors that correspond to these cell types are pheochromocytomas, extra-adrenal paragangliomas, and medullary thyroid carcinomas. Although controversies concerning embryological origin appear to have mostly been resolved, questions persist concerning the pathobiology of each tumor type and its basis in neural crest embryology. Here we present a brief history of the work on neural crest development, both in general and in application to the endocrine system. In particular, we present findings related to the plasticity and pluripotency of neural crest cells as well as a discussion of several different neural crest tumors in the endocrine system.

  17. Should I stay or should I go? Cadherin function and regulation in the neural crest.

    Science.gov (United States)

    Taneyhill, Lisa A; Schiffmacher, Andrew T

    2017-03-02

    Our increasing comprehension of neural crest cell development has reciprocally advanced our understanding of cadherin expression, regulation, and function. As a transient population of multipotent stem cells that significantly contribute to the vertebrate body plan, neural crest cells undergo a variety of transformative processes and exhibit many cellular behaviors, including epithelial-to-mesenchymal transition (EMT), motility, collective cell migration, and differentiation. Multiple studies have elucidated regulatory and mechanistic details of specific cadherins during neural crest cell development in a highly contextual manner. Collectively, these results reveal that gradual changes within neural crest cells are accompanied by often times subtle, yet important, alterations in cadherin expression and function. The primary focus of this review is to coalesce recent data on cadherins in neural crest cells, from their specification to their emergence as motile cells soon after EMT, and to highlight the complexities of cadherin expression beyond our current perceptions, including the hypothesis that the neural crest EMT is a transition involving a predominantly singular cadherin switch. Further advancements in genetic approaches and molecular techniques will provide greater opportunities to integrate data from various model systems in order to distinguish unique or overlapping functions of cadherins expressed at any point throughout the ontogeny of the neural crest.

  18. Characterization of the trunk neural crest in the bamboo shark, Chiloscyllium punctatum.

    Science.gov (United States)

    Juarez, Marilyn; Reyes, Michelle; Coleman, Tiffany; Rotenstein, Lisa; Sao, Sothy; Martinez, Darwin; Jones, Matthew; Mackelprang, Rachel; De Bellard, Maria Elena

    2013-10-01

    The neural crest is a population of mesenchymal cells that after migrating from the neural tube gives rise to structure and cell types: the jaw, part of the peripheral ganglia, and melanocytes. Although much is known about neural crest development in jawed vertebrates, a clear picture of trunk neural crest development for elasmobranchs is yet to be developed. Here we present a detailed study of trunk neural crest development in the bamboo shark, Chiloscyllium punctatum. Vital labeling with dioctadecyl tetramethylindocarbocyanine perchlorate (DiI) and in situ hybridization using cloned Sox8 and Sox9 probes demonstrated that trunk neural crest cells follow a pattern similar to the migratory paths already described in zebrafish and amphibians. We found shark trunk neural crest along the rostral side of the somites, the ventromedial pathway, the branchial arches, the gut, the sensory ganglia, and the nerves. Interestingly, C. punctatum Sox8 and Sox9 sequences aligned with vertebrate SoxE genes, but appeared to be more ancient than the corresponding vertebrate paralogs. The expression of these two SoxE genes in trunk neural crest cells, especially Sox9, matched the Sox10 migratory patterns observed in teleosts. Also of interest, we observed DiI cells and Sox9 labeling along the lateral line, suggesting that in C. punctatum, glial cells in the lateral line are likely of neural crest origin. Although this has been observed in other vertebrates, we are the first to show that the pattern is present in cartilaginous fishes. These findings demonstrate that trunk neural crest cell development in C. punctatum follows the same highly conserved migratory pattern observed in jawed vertebrates. © 2013 Wiley Periodicals, Inc.

  19. A novel role for Lh3 dependent ECM modifications during neural crest cell migration in zebrafish.

    Directory of Open Access Journals (Sweden)

    Santanu Banerjee

    Full Text Available During vertebrate development, trunk neural crest cells delaminate along the entire length of the dorsal neural tube and initially migrate as a non-segmented sheet. As they enter the somites, neural crest cells rearrange into spatially restricted segmental streams. Extracellular matrix components are likely to play critical roles in this transition from a sheet-like to a stream-like mode of migration, yet the extracellular matrix components and their modifying enzymes critical for this transition are largely unknown. Here, we identified the glycosyltransferase Lh3, known to modify extracellular matrix components, and its presumptive substrate Collagen18A1, to provide extrinsic signals critical for neural crest cells to transition from a sheet-like migration behavior to migrating as a segmental stream. Using live cell imaging we show that in lh3 null mutants, neural crest cells fail to transition from a sheet to a stream, and that they consequently enter the somites as multiple streams, or stall shortly after entering the somites. Moreover, we demonstrate that transgenic expression of lh3 in a small subset of somitic cells adjacent to where neural crest cells switch from sheet to stream migration restores segmental neural crest cell migration. Finally, we show that knockdown of the presumptive Lh3 substrate Collagen18A1 recapitulates the neural crest cell migration defects observed in lh3 mutants, consistent with the notion that Lh3 exerts its effect on neural crest cell migration by regulating post-translational modifications of Collagen18A1. Together these data suggest that Lh3-Collagen18A1 dependent ECM modifications regulate the transition of trunk neural crest cells from a non-segmental sheet like migration mode to a segmental stream migration mode.

  20. A novel role for Lh3 dependent ECM modifications during neural crest cell migration in zebrafish.

    Science.gov (United States)

    Banerjee, Santanu; Isaacman-Beck, Jesse; Schneider, Valerie A; Granato, Michael

    2013-01-01

    During vertebrate development, trunk neural crest cells delaminate along the entire length of the dorsal neural tube and initially migrate as a non-segmented sheet. As they enter the somites, neural crest cells rearrange into spatially restricted segmental streams. Extracellular matrix components are likely to play critical roles in this transition from a sheet-like to a stream-like mode of migration, yet the extracellular matrix components and their modifying enzymes critical for this transition are largely unknown. Here, we identified the glycosyltransferase Lh3, known to modify extracellular matrix components, and its presumptive substrate Collagen18A1, to provide extrinsic signals critical for neural crest cells to transition from a sheet-like migration behavior to migrating as a segmental stream. Using live cell imaging we show that in lh3 null mutants, neural crest cells fail to transition from a sheet to a stream, and that they consequently enter the somites as multiple streams, or stall shortly after entering the somites. Moreover, we demonstrate that transgenic expression of lh3 in a small subset of somitic cells adjacent to where neural crest cells switch from sheet to stream migration restores segmental neural crest cell migration. Finally, we show that knockdown of the presumptive Lh3 substrate Collagen18A1 recapitulates the neural crest cell migration defects observed in lh3 mutants, consistent with the notion that Lh3 exerts its effect on neural crest cell migration by regulating post-translational modifications of Collagen18A1. Together these data suggest that Lh3-Collagen18A1 dependent ECM modifications regulate the transition of trunk neural crest cells from a non-segmental sheet like migration mode to a segmental stream migration mode.

  1. Neural crest does not contribute to the neck and shoulder in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Epperlein, Hans-Henning; Khattak, Shahryar; Knapp, Dunja; Tanaka, Elly M; Malashichev, Yegor B

    2012-01-01

    A major step during the evolution of tetrapods was their transition from water to land. This process involved the reduction or complete loss of the dermal bones that made up connections to the skull and a concomitant enlargement of the endochondral shoulder girdle. In the mouse the latter is derived from three separate embryonic sources: lateral plate mesoderm, somites, and neural crest. The neural crest was suggested to sustain the muscle attachments. How this complex composition of the endochondral shoulder girdle arose during evolution and whether it is shared by all tetrapods is unknown. Salamanders that lack dermal bone within their shoulder girdle were of special interest for a possible contribution of the neural crest to the endochondral elements and muscle attachment sites, and we therefore studied them in this context. We grafted neural crest from GFP+ fluorescent transgenic axolotl (Ambystoma mexicanum) donor embryos into white (d/d) axolotl hosts and followed the presence of neural crest cells within the cartilage of the shoulder girdle and the connective tissue of muscle attachment sites of the neck-shoulder region. Strikingly, neural crest cells did not contribute to any part of the endochondral shoulder girdle or to the connective tissue at muscle attachment sites in axolotl. Our results in axolotl suggest that neural crest does not serve a general function in vertebrate shoulder muscle attachment sites as predicted by the "muscle scaffold theory," and that it is not necessary to maintain connectivity of the endochondral shoulder girdle to the skull. Our data support the possibility that the contribution of the neural crest to the endochondral shoulder girdle, which is observed in the mouse, arose de novo in mammals as a developmental basis for their skeletal synapomorphies. This further supports the hypothesis of an increased neural crest diversification during vertebrate evolution.

  2. Neural crest does not contribute to the neck and shoulder in the axolotl (Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Hans-Henning Epperlein

    Full Text Available BACKGROUND: A major step during the evolution of tetrapods was their transition from water to land. This process involved the reduction or complete loss of the dermal bones that made up connections to the skull and a concomitant enlargement of the endochondral shoulder girdle. In the mouse the latter is derived from three separate embryonic sources: lateral plate mesoderm, somites, and neural crest. The neural crest was suggested to sustain the muscle attachments. How this complex composition of the endochondral shoulder girdle arose during evolution and whether it is shared by all tetrapods is unknown. Salamanders that lack dermal bone within their shoulder girdle were of special interest for a possible contribution of the neural crest to the endochondral elements and muscle attachment sites, and we therefore studied them in this context. RESULTS: We grafted neural crest from GFP+ fluorescent transgenic axolotl (Ambystoma mexicanum donor embryos into white (d/d axolotl hosts and followed the presence of neural crest cells within the cartilage of the shoulder girdle and the connective tissue of muscle attachment sites of the neck-shoulder region. Strikingly, neural crest cells did not contribute to any part of the endochondral shoulder girdle or to the connective tissue at muscle attachment sites in axolotl. CONCLUSIONS: Our results in axolotl suggest that neural crest does not serve a general function in vertebrate shoulder muscle attachment sites as predicted by the "muscle scaffold theory," and that it is not necessary to maintain connectivity of the endochondral shoulder girdle to the skull. Our data support the possibility that the contribution of the neural crest to the endochondral shoulder girdle, which is observed in the mouse, arose de novo in mammals as a developmental basis for their skeletal synapomorphies. This further supports the hypothesis of an increased neural crest diversification during vertebrate evolution.

  3. 75 FR 32818 - National Endowment for the Arts; National Council on the Arts 170th Meeting

    Science.gov (United States)

    2010-06-09

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; National Council on the Arts 170th Meeting... hereby given that a meeting of the National Council on the Arts will be held on June 24-25, 2009 in Rooms... of this meeting, from 12:30 p.m.-2 p.m. on June 24th, will be closed for National Medal of...

  4. Endowments, power, and democracy: Political economy of multilateral commitments on trade in services

    OpenAIRE

    Roy, Martin

    2010-01-01

    In spite of their growing importance in international trade as well as in bilateral and multilateral trade negotiations, services have only attracted limited attention from researchers interested in determinants of trade policies and trade cooperation. This paper seeks to account for countries' varying levels of market access commitments under the multilateral General Agreement on Trade in Services (GATS). I develop an argument suggesting how levels of democracy and factor endowments are asso...

  5. Analysis on the Optimization of New Rural Social Endowment Insurance in Changsha,Zhuzhou and Xiangtan

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On the basis of the investigation on the status quo of pilot area of rural endowment insurance in Changsha,Zhuzhou and Xiangtan,farmers’ demand on insuance in the new pilot area of rural endowment insurance is expounded from two aspects:farmers’ awareness on insurance is increasing gradually;farmers’ ability on insuring is increasing.The growing demand of farmers on insuring and the conflicts between the supply of rural endowment insurance and the system construction are analyzed.The problems are inadequate input of funds,low level of social security;imperfect fund-collecting mechanism,serious vacancy;low level of fund management and operation,poor ability of inflation-proofing and appreciation;backward laws and regulations and instability of system.On the strength of the analysis above,the government should innovate and compound fund-collecting mechanism;establish "G-C-F" three-pillar model and set up "BSI" the third party custodian;accelerate the legislation of new rural pension system so as to push forward the optimization of new rural pension insurance system in Changsha,Zhuzhou and Xiangtan.

  6. Development of Endothelial-Specific Single Inducible Lentiviral Vectors for Genetic Engineering of Endothelial Progenitor Cells.

    Science.gov (United States)

    Yang, Guanghua; Kramer, M Gabriela; Fernandez-Ruiz, Veronica; Kawa, Milosz P; Huang, Xin; Liu, Zhongmin; Prieto, Jesus; Qian, Cheng

    2015-11-27

    Endothelial progenitor cells (EPC) are able to migrate to tumor vasculature. These cells, if genetically modified, can be used as vehicles to deliver toxic material to, or express anticancer proteins in tumor. To test this hypothesis, we developed several single, endothelial-specific, and doxycycline-inducible self-inactivating (SIN) lentiviral vectors. Two distinct expression cassettes were inserted into a SIN-vector: one controlled by an endothelial lineage-specific, murine vascular endothelial cadherin (mVEcad) promoter for the expression of a transactivator, rtTA2S-M2; and the other driven by an inducible promoter, TREalb, for a firefly luciferase reporter gene. We compared the expression levels of luciferase in different vector constructs, containing either the same or opposite orientation with respect to the vector sequence. The results showed that the vector with these two expression cassettes placed in opposite directions was optimal, characterized by a robust induction of the transgene expression (17.7- to 73-fold) in the presence of doxycycline in several endothelial cell lines, but without leakiness when uninduced. In conclusion, an endothelial lineage-specific single inducible SIN lentiviral vector has been developed. Such a lentiviral vector can be used to endow endothelial progenitor cells with anti-tumor properties.

  7. Roles of chromatin remodelers in maintenance mechanisms of multipotency of mouse trunk neural crest cells in the formation of neural crest-derived stem cells.

    Science.gov (United States)

    Fujita, Kyohei; Ogawa, Ryuhei; Kawawaki, Syunsaku; Ito, Kazuo

    2014-08-01

    We analyzed roles of two chromatin remodelers, Chromodomain Helicase DNA-binding protein 7 (CHD7) and SWItch/Sucrose NonFermentable-B (SWI/SNF-B), and Bone Morphogenetic Protein (BMP)/Wnt signaling in the maintenance of the multipotency of mouse trunk neural crest cells, leading to the formation of mouse neural crest-derived stem cells (mouse NCSCs). CHD7 was expressed in the undifferentiated neural crest cells and in the dorsal root ganglia (DRG) and sciatic nerve, typical tissues containing NCSCs. BMP/Wnt signaling stimulated the expression of CHD7 and participated in maintaining the multipotency of neural crest cells. Furthermore, the promotion of CHD7 expression maintained the multipotency of these cells. The inhibition of CHD7 and SWI/SNF-B expression significantly suppressed the maintenance of the multipotency of these cells. In addition, BMP/Wnt treatment promoted CHD7 expression and caused the increase of the percentage of multipotent cells in DRG. Thus, the present data suggest that the chromatin remodelers as well as BMP/Wnt signaling play essential roles in the maintenance of the multipotency of mouse trunk neural crest cells and in the formation of mouse NCSCs. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Methods for derivation of multipotent neural crest cells derived from human pluripotent stem cells

    Science.gov (United States)

    Avery, John; Dalton, Stephen

    2016-01-01

    Summary Multipotent, neural crest cells (NCCs) produce a wide-range of cell types during embryonic development. This includes melanocytes, peripheral neurons, smooth muscle cells, osteocytes, chondrocytes and adipocytes. The protocol described here allows for highly-efficient differentiation of human pluripotent stem cells to a neural crest fate within 15 days. This is accomplished under feeder-free conditions, using chemically defined medium supplemented with two small molecule inhibitors that block glycogen synthase kinase 3 (GSK3) and bone morphogenic protein (BMP) signaling. This technology is well-suited as a platform to understand in greater detail the pathogenesis of human disease associated with impaired neural crest development/migration. PMID:25986498

  9. Quill injury - cause od death of captive indian crested porcupine(Hystrix indica, Kerr, 1792

    Directory of Open Access Journals (Sweden)

    Tanja Švara

    2015-03-01

    Full Text Available Indian crested porcupine (Hystrix indica is a member of the family of Old World porcupines (Hystricidae. Its body is covered with multiple layers of quills, which serve for warning and attack if animal is threatened. However, the literature data on injuries caused by Indian crested porcupine are absent. We describe pathomorphological lesions in an Indian crested porcupine from the Ljubljana Zoo, which died after a fight with a younger male that caused a perforative quill injury of the thoracic wall, followed by septicaemia. Macroscopic, microscopic and bacteriological findings were detailed

  10. Hematopoietic progenitor migration to the adult thymus

    OpenAIRE

    Zlotoff, Daniel A.; Bhandoola, Avinash

    2011-01-01

    While most hematopoietic lineages develop in the bone marrow (BM), T cells uniquely complete their development in the specialized environment of the thymus. Hematopoietic stem cells with long-term self-renewal capacity are not present in the thymus. As a result, continuous T cell development requires that BM-derived progenitors be imported into the thymus throughout adult life. The process of thymic homing begins with the mobilization of progenitors out of the bone marrow, continues with thei...

  11. A novel role for MuSK and non-canonical Wnt signaling during segmental neural crest cell migration.

    Science.gov (United States)

    Banerjee, Santanu; Gordon, Laura; Donn, Thomas M; Berti, Caterina; Moens, Cecilia B; Burden, Steven J; Granato, Michael

    2011-08-01

    Trunk neural crest cells delaminate from the dorsal neural tube as an uninterrupted sheet; however, they convert into segmentally organized streams before migrating through the somitic territory. These neural crest cell streams join the segmental trajectories of pathfinding spinal motor axons, suggesting that interactions between these two cell types might be important for neural crest cell migration. Here, we show that in the zebrafish embryo migration of both neural crest cells and motor axons is temporally synchronized and spatially restricted to the center of the somite, but that motor axons are dispensable for segmental neural crest cell migration. Instead, we find that muscle-specific receptor kinase (MuSK) and its putative ligand Wnt11r are crucial for restricting neural crest cell migration to the center of each somite. Moreover, we find that blocking planar cell polarity (PCP) signaling in somitic muscle cells also results in non-segmental neural crest cell migration. Using an F-actin biosensor we show that in the absence of MuSK neural crest cells fail to retract non-productive leading edges, resulting in non-segmental migration. Finally, we show that MuSK knockout mice display similar neural crest cell migration defects, suggesting a novel, evolutionarily conserved role for MuSK in neural crest migration. We propose that a Wnt11r-MuSK dependent, PCP-like pathway restricts neural crest cells to their segmental path.

  12. Distinct enhancers at the Pax3 locus can function redundantly to regulate neural tube and neural crest expressions.

    Science.gov (United States)

    Degenhardt, Karl R; Milewski, Rita C; Padmanabhan, Arun; Miller, Mayumi; Singh, Manvendra K; Lang, Deborah; Engleka, Kurt A; Wu, Meilin; Li, Jun; Zhou, Diane; Antonucci, Nicole; Li, Li; Epstein, Jonathan A

    2010-03-15

    Pax3 is a transcription factor expressed in somitic mesoderm, dorsal neural tube and pre-migratory neural crest during embryonic development. We have previously identified cis-acting enhancer elements within the proximal upstream genomic region of Pax3 that are sufficient to direct functional expression of Pax3 in neural crest. These elements direct expression of a reporter gene to pre-migratory neural crest in transgenic mice, and transgenic expression of a Pax3 cDNA using these elements is sufficient to rescue neural crest development in mice otherwise lacking endogenous Pax3. We show here that deletion of these enhancer sequences by homologous recombination is insufficient to abrogate neural crest expression of Pax3 and results in viable mice. We identify a distinct enhancer in the fourth intron that is also capable of mediating neural crest expression in transgenic mice and zebrafish. Our analysis suggests the existence of functionally redundant neural crest enhancer modules for Pax3.

  13. Supernova Remnant Progenitor Masses in M31

    CERN Document Server

    Jennings, Zachary G; Murphy, Jeremiah W; Dalcanton, Julianne J; Gilbert, Karoline M; Dolphin, Andrew E; Fouesneau, Morgan; Weisz, Daniel R

    2012-01-01

    Using HST photometry, we age-date 59 supernova remnants (SNRs) in the spiral galaxy M31 and use these ages to estimate zero-age main sequence masses (MZAMS) for their progenitors. To accomplish this, we create color-magnitude diagrams (CMDs) and use CMD fitting to measure the recent star formation history (SFH) of the regions surrounding cataloged SNR sites. We identify any young coeval population that likely produced the progenitor star and assign an age and uncertainty to that population. Application of stellar evolution models allows us to infer the MZAMS from this age. Because our technique is not contingent on precise location of the progenitor star, it can be applied to the location of any known SNR. We identify significant young SF around 53 of the 59 SNRs and assign progenitor masses to these, representing a factor of 2 increase over currently measured progenitor masses. We consider the remaining 6 SNRs as either probable Type Ia candidates or the result of core-collapse progenitors that have escaped ...

  14. Trunk lateral cells are neural crest-like cells in the ascidian Ciona intestinalis: insights into the ancestry and evolution of the neural crest.

    Science.gov (United States)

    Jeffery, William R; Chiba, Takuto; Krajka, Florian Razy; Deyts, Carole; Satoh, Nori; Joly, Jean-Stéphane

    2008-12-01

    Neural crest-like cells (NCLC) that express the HNK-1 antigen and form body pigment cells were previously identified in diverse ascidian species. Here we investigate the embryonic origin, migratory activity, and neural crest related gene expression patterns of NCLC in the ascidian Ciona intestinalis. HNK-1 expression first appeared at about the time of larval hatching in dorsal cells of the posterior trunk. In swimming tadpoles, HNK-1 positive cells began to migrate, and after metamorphosis they were localized in the oral and atrial siphons, branchial gill slits, endostyle, and gut. Cleavage arrest experiments showed that NCLC are derived from the A7.6 cells, the precursors of trunk lateral cells (TLC), one of the three types of migratory mesenchymal cells in ascidian embryos. In cleavage arrested embryos, HNK-1 positive TLC were present on the lateral margins of the neural plate and later became localized adjacent to the posterior sensory vesicle, a staging zone for their migration after larval hatching. The Ciona orthologues of seven of sixteen genes that function in the vertebrate neural crest gene regulatory network are expressed in the A7.6/TLC lineage. The vertebrate counterparts of these genes function downstream of neural plate border specification in the regulatory network leading to neural crest development. The results suggest that NCLC and neural crest cells may be homologous cell types originating in the common ancestor of tunicates and vertebrates and support the possibility that a putative regulatory network governing NCLC development was co-opted to produce neural crest cells during vertebrate evolution.

  15. Biology of nesting crested, least, and whiskered auklets at Buldir Island, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — During avifaunal investigations at Buldir Island 1974-1976, some aspects of the biology of Crested, Least, and Whiskered Auklets were investigated in a colony where...

  16. Project proposal : control of crested wheatgrass by relocation of black-tailed prairie dogs

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Proposal for research at the Rocky Mountain Arsenal to examine experimental means of controlling crested wheatgrass while establishing relocated prairie dog colonies...

  17. A potential inhibitory function of draxin in regulating mouse trunk neural crest migration.

    Science.gov (United States)

    Zhang, Sanbing; Su, Yuhong; Gao, Jinbao; Zhang, Chenbing; Tanaka, Hideaki

    2017-01-01

    Draxin is a repulsive axon guidance protein that plays important roles in the formation of three commissures in the central nervous system and dorsal interneuron 3 (dI3) in the chick spinal cord. In the present study, we report the expression pattern of mouse draxin in the embryonic mouse trunk spinal cord. In the presence of draxin, the longest net migration length of a migrating mouse trunk neural crest cell was significantly reduced. In addition, the relative number of apolar neural crest cells increased as the draxin treatment time increased. Draxin caused actin cytoskeleton rearrangement in the migrating trunk neural crest cells. Our data suggest that draxin may regulate mouse trunk neural crest cell migration by the rearrangement of cell actin cytoskeleton and by reducing the polarization activity of these cells subsequently.

  18. 78 FR 26358 - Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy; Notice of Meeting With...

    Science.gov (United States)

    2013-05-06

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy...), on the Eagle Mountain Pumped Storage Hydroelectric Project. e. All local, state, and federal...

  19. First report and breeding record of the Chinese Crested Tern Thalasseus bernsteini on the Korean Peninsula

    Directory of Open Access Journals (Sweden)

    Se-Kyu Song

    2017-06-01

    Full Text Available The Chinese Crested Tern Thalasseus bernsteini is a critically endangered species (as designated by the IUCN (International Union for Conservation of Nature and Natural Resources. This report expands the known breeding grounds of these birds eastward. An individual of the Chinese Crested Tern was first observed at an uninhabited island of Jeollanam-do in Korea on April 28, 2016. On May 9, 2016 five Chinese Crested Terns (consisting of 2 breeding pairs and a single bird were observed. Nests from the breeding pairs were found, at a distance of 0.6 m from each other; each pair was observed incubating one egg in the nest. To our knowledge, this is the easternmost record of breeding grounds for the Chinese Crested Tern.

  20. 76 FR 22393 - Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy; Notice of Cancellation...

    Science.gov (United States)

    2011-04-21

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy... and Wildlife Service for the proposed Eagle Mountain Pumped Storage Hydroelectric Project....

  1. 77 FR 47628 - Eagle Mountain Pumped Storage Hydroelectric Project; Eagle Crest Energy; Notice of Meeting...

    Science.gov (United States)

    2012-08-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project; Eagle Crest Energy... Management Act and the Federal Power Act), on the Eagle Mountain Pumped Storage Hydroelectric...

  2. Induction of cranial and posterior trunk neural crest by exogenous retinoic acid in zebrafish

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Retinoic acid (RA) plays an important role in development of vertebrate embryos. We demonstrate impacts of exogenous RA on the formation of neural crest cells in zebrafish using specific neural crest markers sox9b and crestin. Treatment with all-trans RA at 10?7 mmol/L at 50% epiboly induces sox9b expression in the forebrain and crestin expression in the forebrain and midbrain, resulting in significant increase of pigment cells in the head derived from the cranial neural crest. In addition, RA treatment induces expression of sox9b and crestin in the caudal marginal cells of the neuroectoderm during early segmentation. Earlier commitment of these cells to the neural crest fate in the posterior margins leads to abnormal development of the posterior body, probably by preventing mingling of ventral derived and dorsal-derived cells during the formation of the tailbud.

  3. 2011 update to crested wheatgrass control and monitoring Benton Lake Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Crested wheatgrass (CWG) was planted on Benton Lake NWR at least 30 years ago, presumably to stabilize the soil where it had been disturbed in the process of...

  4. 2009 update to crested wheatgrass control and monitoring Benton Lake Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Crested wheatgrass (CWG) was planted on Benton Lake NWR at least 30 years ago, presumably to stabilize the soil where it had been disturbed in the process of...

  5. 2010 update to crested wheatgrass control and monitoring Benton Lake Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Crested wheatgrass (CWG) was planted on Benton Lake NWR at least 30 years ago, presumably to stabilize the soil where it had been disturbed in the process of...

  6. Sex-related gene and sex identification of Crested Ibis Nipponia nippon (Ciconiiformes: Threskiornithidae)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Crested Ibis (Nipponia nippon) is a critical endangeredspecies of the world. At present, a reintroduction program will be conducted to save this species essentially. However, because the Crested Ibise is a sexual alike bird, it is very difficult to identify the sex from the morphological character. In order to identify the sex easily and select the right individuals for captive breeding and reintroduction, the sex related gene on W chromosome was amplified and the sex of three Crested Ibises were also identified in the present study. The 262bp fragment was also sequenced, and we found that there were 13 different nucleotide sites with 2.25 of transition/transversion based on the comparison with that of the Oriental White Stork. The sequence will also provide a theoretic base for further designing specific primer for sex related gene in the Crested Ibis.

  7. A Comparative Study of Growth Patterns in Crested Langurs and Vervet Monkeys

    Directory of Open Access Journals (Sweden)

    Debra R. Bolter

    2011-01-01

    Full Text Available The physical growth patterns of crested langurs and vervet monkeys are investigated for several unilinear dimensions. Long bone lengths, trunk height, foot length, epiphyseal fusion of the long bones and the pelvis, and cranial capacity are compared through six dental growth stages in male Trachypithecus cristatus (crested langurs and Cercopithecus aethiops (vervet monkeys. Results show that the body elements of crested langurs mature differently than those of vervets. In some dimensions, langurs and vervets grow comparably, in others vervets attain adult values in advance of crested langurs, and in one feature the langurs are accelerated. Several factors may explain this difference, including phylogeny, diet, ecology, and locomotion. This study proposes that locomotor requirements affect differences in somatic growth between the species.

  8. Crestospheres: Long-Term Maintenance of Multipotent, Premigratory Neural Crest Stem Cells

    Directory of Open Access Journals (Sweden)

    Laura Kerosuo

    2015-10-01

    Full Text Available Premigratory neural crest cells comprise a transient, embryonic population that arises within the CNS, but subsequently migrates away and differentiates into many derivatives. Previously, premigratory neural crest could not be maintained in a multipotent, adhesive state without spontaneous differentiation. Here, we report conditions that enable maintenance of neuroepithelial “crestospheres” that self-renew and retain multipotency for weeks. Moreover, under differentiation conditions, these cells can form multiple derivatives in vitro and in vivo after transplantation into chick embryos. Similarly, human embryonic stem cells directed to a neural crest fate can be maintained as crestospheres and subsequently differentiated into several derivatives. By devising conditions that maintain the premigratory state in vitro, these results demonstrate that neuroepithelial neural crest precursors are capable of long-term self-renewal. This approach will help uncover mechanisms underlying their developmental potential, differentiation and, together with the induced pluripotent stem cell techniques, the pathology of human neurocristopathies.

  9. Apollo 15 Onboard Photo: Earth's Crest Over the Lunar Horizon

    Science.gov (United States)

    1971-01-01

    This view of the Earth's crest over the lunar horizon was taken during the Apollo 15 lunar landing mission. Apollo 15 launched from the Kennedy Space Center (KSC) on July 26, 1971 via a Saturn V launch vehicle. Aboard was a crew of three astronauts including David R. Scott, Mission Commander; James B. Irwin, Lunar Module Pilot; and Alfred M. Worden, Command Module Pilot. The first mission designed to explore the Moon over longer periods, greater ranges and with more instruments for the collection of scientific data than on previous missions, the mission included the introduction of a $40,000,000 lunar roving vehicle (LRV) that reached a top speed of 16 kph (10 mph) across the Moon's surface. The successful Apollo 15 lunar landing mission was the first in a series of three advanced missions planned for the Apollo program. The primary scientific objectives were to observe the lunar surface, survey and sample material and surface features in a preselected area of the Hadley-Apennine region, setup and activation of surface experiments and conduct in-flight experiments and photographic tasks from lunar orbit. Apollo 15 televised the first lunar liftoff and recorded a walk in deep space by Alfred Worden. Both the Saturn V rocket and the LRV were developed at the Marshall Space Flight Center.

  10. Generating trunk neural crest from human pluripotent stem cells.

    Science.gov (United States)

    Huang, Miller; Miller, Matthew L; McHenry, Lauren K; Zheng, Tina; Zhen, Qiqi; Ilkhanizadeh, Shirin; Conklin, Bruce R; Bronner, Marianne E; Weiss, William A

    2016-01-27

    Neural crest cells (NCC) are stem cells that generate different lineages, including neuroendocrine, melanocytic, cartilage, and bone. The differentiation potential of NCC varies according to the level from which cells emerge along the neural tube. For example, only anterior "cranial" NCC form craniofacial bone, whereas solely posterior "trunk" NCC contribute to sympathoadrenal cells. Importantly, the isolation of human fetal NCC carries ethical and scientific challenges, as NCC induction typically occur before pregnancy is detectable. As a result, current knowledge of NCC biology derives primarily from non-human organisms. Important differences between human and non-human NCC, such as expression of HNK1 in human but not mouse NCC, suggest a need to study human NCC directly. Here, we demonstrate that current protocols to differentiate human pluripotent stem cells (PSC) to NCC are biased toward cranial NCC. Addition of retinoic acid drove trunk-related markers and HOX genes characteristic of a posterior identity. Subsequent treatment with bone morphogenetic proteins (BMPs) enhanced differentiation to sympathoadrenal cells. Our approach provides methodology for detailed studies of human NCC, and clarifies roles for retinoids and BMPs in the differentiation of human PSC to trunk NCC and to sympathoadrenal lineages.

  11. Distress prevention by grooming others in crested black macaques.

    Science.gov (United States)

    Aureli, Filippo; Yates, Kerrie

    2010-02-23

    Allogrooming is probably one of the most common and most studied social behaviours in a variety of animals. Whereas the short-term benefits for the groomee have often been investigated, little is known about the effects for the groomer. Our study focused on the short-term effects of grooming another group member in seven adult female crested black macaques (Macaca nigra). We found reductions in self-directed behaviour, an indicator of anxiety, and aggressive tendencies soon after grooming, when compared to matched-control periods. These findings can be interpreted as evidence of distress prevention, possibly mediated by an increase in tolerance. Indeed, a former groomee was more likely to be the nearest neighbour of the former groomer in the 10 min after grooming ended. Thus, the role of grooming in short-term distress alleviation can be applicable to the groomer as well as the groomee. These short-term effects, together with the longer-term effects of large and/or strong grooming networks confirm that grooming, as well as receiving grooming, has great importance for social dynamics.

  12. [Incidence of Upupicola upupae in the crest of the hoopoe].

    Science.gov (United States)

    Mester, H

    1977-11-01

    Hopoes belonging to waves of migrants through the Balearic Islands in August and September showed high rates of infestation by Upupicola upupae (77--85 p. c.). The parasite species was almost exclusively confined to the long and mobile feathers of the bird's crown. And at this time of the year the Mallophaga had put their egg cases on the crest feathers, too. A mean of 7 feather-lice was found at this localisation in 8 positive cases sampled. As some of the birds were moulting just these parts of their plumage, a relative high loss of the lice egg masses had to be expected. Evidently, in these cases, the lice didn't adaptively synchronise laying with the period during which moulting occurs. The wings of hopoes are conspiciously barred glossy-black and white. Here the relative dark coloured lice were sitting predominantly in a dark feather area. In these places they were much less visble than on a neighbouring white area. Thus the parasites hide themselves according to their colour.

  13. Ets-1 confers cranial features on neural crest delamination.

    Directory of Open Access Journals (Sweden)

    Eric Théveneau

    Full Text Available Neural crest cells (NCC have the particularity to invade the environment where they differentiate after separation from the neuroepithelium. This process, called delamination, is strikingly different between cranial and trunk NCCs. If signalings controlling slow trunk delamination start being deciphered, mechanisms leading to massive and rapid cranial outflow are poorly documented. Here, we show that the chick cranial NCCs delamination is the result of two events: a substantial cell mobilization and an epithelium to mesenchyme transition (EMT. We demonstrate that ets-1, a transcription factor specifically expressed in cranial NCCs, is responsible for the former event by recruiting massively cranial premigratory NCCs independently of the S-phase of the cell cycle and by leading the gathered cells to straddle the basal lamina. However, it does not promote the EMT process alone but can cooperate with snail-2 (previously called slug to this event. Altogether, these data lead us to propose that ets-1 plays a pivotal role in conferring specific cephalic characteristics on NCC delamination.

  14. The ciliary baton: orchestrating neural crest cell development.

    Science.gov (United States)

    Chang, Ching-Fang; Schock, Elizabeth N; Attia, Aria C; Stottmann, Rolf W; Brugmann, Samantha A

    2015-01-01

    Primary cilia are cell surface, microtubule-based organelles that dynamically extend from cells to receive and process molecular and mechanical signaling cues. In the last decade, this organelle has gained increasing popularity due to its ability to act as a cellular antenna, receive molecular stimuli, and respond to the cell's environment. A growing field of data suggests that various tissues utilize and interpret the loss of cilia in different ways. Thus, careful examination of the role of cilia on individual cell types and tissues is necessary. Neural crest cells (NCCs) are an excellent example of cells that survey their environment for developmental cues. In this review, we discuss how NCCs utilize primary cilia during their ontogenic development, paying special attention to the role primary cilia play in processing developmental signals required for NCC specification, migration, proliferation, and differentiation. We also discuss how the loss of functional cilia on cranial and trunk NCCs affects the development of various organ systems to which they contribute. A deeper understanding of ciliary function could contribute greatly to understanding the molecular mechanisms guiding NCC development and differentiation. Furthermore, superimposing the ciliary contribution on our current understanding of NCC development identifies new avenues for therapeutic intervention in neurocristopathies. © 2015 Elsevier Inc. All rights reserved.

  15. Dance Drama Crested Ibises Staged at National Center for the Performing Arts

    Institute of Scientific and Technical Information of China (English)

    Our; Staff; Reporter

    2015-01-01

    "By the floating mist of the lake,several pink feathered crested ibises are flying slowly across the crimson rays of the setting sun,causing rhythmic ripples with their red feet,quietly and elegantly……"The premiere of a fascinating and poetic dance drama was staged at the Opera House of the National Center for the Performing Arts(NCPA)on December 9,2014.Crested Ibises,jointly

  16. A PTK7/Ror2 Co-Receptor Complex Affects Xenopus Neural Crest Migration.

    Directory of Open Access Journals (Sweden)

    Martina Podleschny

    Full Text Available Neural crest cells are a highly migratory pluripotent cell population that generates a wide array of different cell types and failure in their migration can result in severe birth defects and malformation syndromes. Neural crest migration is controlled by various means including chemotaxis, repellent guidance cues and cell-cell interaction. Non-canonical Wnt PCP (planar cell polarity signaling has previously been shown to control cell-contact mediated neural crest cell guidance. PTK7 (protein tyrosine kinase 7 is a transmembrane pseudokinase and a known regulator of Wnt/PCP signaling, which is expressed in Xenopus neural crest cells and required for their migration. PTK7 functions as a Wnt co-receptor; however, it remains unclear by which means PTK7 affects neural crest migration. Expressing fluorescently labeled proteins in Xenopus neural crest cells we find that PTK7 co-localizes with the Ror2 Wnt-receptor. Further, co-immunoprecipitation experiments demonstrate that PTK7 interacts with Ror2. The PTK7/Ror2 interaction is likely relevant for neural crest migration, because Ror2 expression can rescue the PTK7 loss of function migration defect. Live cell imaging of explanted neural crest cells shows that PTK7 loss of function affects the formation of cell protrusions as well as cell motility. Co-expression of Ror2 can rescue these defects. In vivo analysis demonstrates that a kinase dead Ror2 mutant cannot rescue PTK7 loss of function. Thus, our data suggest that Ror2 can substitute for PTK7 and that the signaling function of its kinase domain is required for this effect.

  17. BASIC CRITERIA OF IRANIAN COMMERCIAL TOOTHPASTES AND AN ADA APPROVED BRAND (CREST)

    OpenAIRE

    2003-01-01

    Introduction: The effectiveness of fluorided toothpastes in reducing dental caries is well-documented, However not all fluorided toothpastes are equally effective. The objective of this study was to compare some essential criteria of six different toothpastes manufactured in Iran with one brand of ADA approved toothpaste (Crest). Methods. Six commercial toothpastes produced in Iran named as Paveh, Puneh, Nasim, Darugar, golpasand and saviz were compared with Crest in three subjects as fo...

  18. Crested wheatgrass (Agropyron cristatum) seedings in Western Colorado: What can we learn?

    OpenAIRE

    James Dollerschell; Anna Lincoln; Amanda Clements; M. Nikki Grant-Hoffman

    2012-01-01

    Non-native species have been widely transported, becoming components of ecosystems worldwide. In some cases this can change thestructure and function of an ecosystem. Crested wheatgrass (Agropyron cristatum, Agropyron spp.) was introduced into the Western U.S. inthe late 18th and early 19th centuries. Since introduction, it has been planted in western rangelands currently occupying millions of acres.Crested wheatgrass causes significant changes in areas where it dominates the vegetation, and ...

  19. CREST maps somatic structural variation in cancer genomes with base-pair resolution

    OpenAIRE

    2011-01-01

    We developed CREST (Clipping REveals STructure), an algorithm that uses next-generation sequencing reads with partial alignments to a reference genome to directly map structural variations at the nucleotide level of resolution. Application of CREST to whole-genome sequencing data from five pediatric T-lineage acute lymphoblastic leukemias (T-ALLs) and a human melanoma cell line, COLO-829, identified 160 somatic structural variations. Experimental validation exceeded 80% demonstrating that CRE...

  20. Transcriptome analysis reveals novel players in the cranial neural crest gene regulatory network

    OpenAIRE

    Simões-Costa, Marcos; Tan-Cabugao, Joanne; Antoshechkin, Igor; Sauka-Spengler, Tatjana; Bronner, Marianne E.

    2014-01-01

    The neural crest is an embryonic stem cell population that gives rise to a multitude of derivatives. In particular, the cranial neural crest (CNC) is unique in its ability to contribute to both facial skeleton and peripheral ganglia. To gain further insight into the molecular underpinnings that distinguish the CNC from other embryonic tissues, we have utilized a CNC-specific enhancer as a tool to isolate a pure, region-specific NC subpopulation for transcriptional profiling. The resulting dat...

  1. Isolation and characterization of neural crest-derived stem cells from dental pulp of neonatal mice.

    Directory of Open Access Journals (Sweden)

    Kajohnkiart Janebodin

    Full Text Available Dental pulp stem cells (DPSCs are shown to reside within the tooth and play an important role in dentin regeneration. DPSCs were first isolated and characterized from human teeth and most studies have focused on using this adult stem cell for clinical applications. However, mouse DPSCs have not been well characterized and their origin(s have not yet been elucidated. Herein we examined if murine DPSCs are neural crest derived and determined their in vitro and in vivo capacity. DPSCs from neonatal murine tooth pulp expressed embryonic stem cell and neural crest related genes, but lacked expression of mesodermal genes. Cells isolated from the Wnt1-Cre/R26R-LacZ model, a reporter of neural crest-derived tissues, indicated that DPSCs were Wnt1-marked and therefore of neural crest origin. Clonal DPSCs showed multi-differentiation in neural crest lineage for odontoblasts, chondrocytes, adipocytes, neurons, and smooth muscles. Following in vivo subcutaneous transplantation with hydroxyapatite/tricalcium phosphate, based on tissue/cell morphology and specific antibody staining, the clones differentiated into odontoblast-like cells and produced dentin-like structure. Conversely, bone marrow stromal cells (BMSCs gave rise to osteoblast-like cells and generated bone-like structure. Interestingly, the capillary distribution in the DPSC transplants showed close proximity to odontoblasts whereas in the BMSC transplants bone condensations were distant to capillaries resembling dentinogenesis in the former vs. osteogenesis in the latter. Thus we demonstrate the existence of neural crest-derived DPSCs with differentiation capacity into cranial mesenchymal tissues and other neural crest-derived tissues. In turn, DPSCs hold promise as a source for regenerating cranial mesenchyme and other neural crest derived tissues.

  2. Cranial and trunk neural crest cells use different mechanisms for attachment to extracellular matrices

    OpenAIRE

    Lallier, Thomas; Leblanc, Gabrielle; Artinger, Kristin B.; Bronner-Fraser, Marianne

    1992-01-01

    We have used a quantitative cell attachment assay to compare the interactions of cranial and trunk neural crest cells with the extracellular matrix (ECM) molecules fibronectin, laminin and collagen types I and IV. Antibodies to the β_1 subunit of integrin inhibited attachment under all conditions tested, suggesting that integrins mediate neural crest cell interactions with these ECM molecules. The HNK-1 antibody against a surface carbohydrate epitope under certain conditions inhibited both cr...

  3. Live image profiling of neural crest lineages in zebrafish transgenic lines.

    Science.gov (United States)

    Kwak, Jina; Park, Ok Kyu; Jung, Yoo Jung; Hwang, Byung Joon; Kwon, Seung-Hae; Kee, Yun

    2013-03-01

    Zebrafish transgenic lines are important experimental tools for lineage tracing and imaging studies. It is crucial to precisely characterize the cell lineages labeled in transgenic lines to understand their limitations and thus properly interpret the data obtained from their use; only then can we confidently select a line appropriate for our particular research objectives. Here we profiled the cell lineages labeled in the closely related neural crest transgenic lines Tg(foxd3:GFP), Tg(sox10:eGFP) and Tg(sox10:mRFP). These fish were crossed to generate embryos, in which foxd3 and sox10 transgenic neural crest labeling could be directly compared at the cellular level using live confocal imaging. We have identified key differences in the cell lineages labeled in each line during early neural crest development and demonstrated that the most anterior cranial neural crest cells initially migrating out of neural tube at the level of forebrain and anterior midbrain express sox10:eGFP and sox10:mRFP, but not foxd3:GFP. This differential profile was robustly maintained in the differentiating progeny of the neural crest lineages until 3.5dpf. Our data will enable researchers to make an informed choice in selecting transgenic lines for future neural crest research.

  4. Migratory patterns and developmental potential of trunk neural crest cells in the axolotl embryo.

    Science.gov (United States)

    Epperlein, Hans-Henning; Selleck, Mark A J; Meulemans, Daniel; Mchedlishvili, Levan; Cerny, Robert; Sobkow, Lidia; Bronner-Fraser, Marianne

    2007-02-01

    Using cell markers and grafting, we examined the timing of migration and developmental potential of trunk neural crest cells in axolotl. No obvious differences in pathway choice were noted for DiI-labeling at different lateral or medial positions of the trunk neural folds in neurulae, which contributed not only to neural crest but also to Rohon-Beard neurons. Labeling wild-type dorsal trunks at pre- and early-migratory stages revealed that individual neural crest cells migrate away from the neural tube along two main routes: first, dorsolaterally between the epidermis and somites and, later, ventromedially between the somites and neural tube/notochord. Dorsolaterally migrating crest primarily forms pigment cells, with those from anterior (but not mid or posterior) trunk neural folds also contributing glia and neurons to the lateral line. White mutants have impaired dorsolateral but normal ventromedial migration. At late migratory stages, most labeled cells move along the ventromedial pathway or into the dorsal fin. Contrasting with other anamniotes, axolotl has a minor neural crest contribution to the dorsal fin, most of which arises from the dermomyotome. Taken together, the results reveal stereotypic migration and differentiation of neural crest cells in axolotl that differ from other vertebrates in timing of entry onto the dorsolateral pathway and extent of contribution to some derivatives.

  5. Experimental investigation on discharge coefficient for a combined broad crested weir-box culvert structure

    Science.gov (United States)

    Guven, A.; Hassan, M.; Sabir, Shahin

    2013-09-01

    This study investigates the hydraulic characteristics of simultaneous flow over broad crested weir and through box (square) culverts experimentally. The variation of discharge coefficient (Cd) of the combined structure with various affective parameters such as upstream head, length of culvert, culvert inlet shape, culvert internal dimension, weir crest height, weir side slope angle, and weir width was analyzed. For this purpose 12 glass models of combined broad crested weirs and box culverts were manufactured and tested in a laboratory flume of 12 m. Discharge coefficient predicting equations were developed as a function of the dimensionless terms. The overall results showed that Cd increases as the ratio of the total head of water above the weir crest to the height of the weir crest H/P increases for all the models and for each flow state (weir and combined). Cd values increased as the head increased for all the models tested as culvert flow only, and also with decreasing of the angle between crest of the weir with the sides.

  6. Real time imaging of human progenitor neurogenesis.

    Directory of Open Access Journals (Sweden)

    Thomas M Keenan

    Full Text Available Human neural progenitors are increasingly being employed in drug screens and emerging cell therapies targeted towards neurological disorders where neurogenesis is thought to play a key role including developmental disorders, Alzheimer's disease, and depression. Key to the success of these applications is understanding the mechanisms by which neurons arise. Our understanding of development can provide some guidance but since little is known about the specifics of human neural development and the requirement that cultures be expanded in vitro prior to use, it is unclear whether neural progenitors obey the same developmental mechanisms that exist in vivo. In previous studies we have shown that progenitors derived from fetal cortex can be cultured for many weeks in vitro as undifferentiated neurospheres and then induced to undergo neurogenesis by removing mitogens and exposing them to supportive substrates. Here we use live time lapse imaging and immunocytochemical analysis to show that neural progenitors use developmental mechanisms to generate neurons. Cells with morphologies and marker profiles consistent with radial glia and recently described outer radial glia divide asymmetrically and symmetrically to generate multipolar intermediate progenitors, a portion of which express ASCL1. These multipolar intermediate progenitors subsequently divide symmetrically to produce CTIP2(+ neurons. This 3-cell neurogenic scheme echoes observations in rodents in vivo and in human fetal slice cultures in vitro, providing evidence that hNPCs represent a renewable and robust in vitro assay system to explore mechanisms of human neurogenesis without the continual need for fresh primary human fetal tissue. Knowledge provided by this and future explorations of human neural progenitor neurogenesis will help maximize the safety and efficacy of new stem cell therapies by providing an understanding of how to generate physiologically-relevant cell types that maintain their

  7. An exclusively mesodermal origin of fin mesenchyme demonstrates that zebrafish trunk neural crest does not generate ectomesenchyme.

    Science.gov (United States)

    Lee, Raymond Teck Ho; Knapik, Ela W; Thiery, Jean Paul; Carney, Thomas J

    2013-07-01

    The neural crest is a multipotent stem cell population that arises from the dorsal aspect of the neural tube and generates both non-ectomesenchymal (melanocytes, peripheral neurons and glia) and ectomesenchymal (skeletogenic, odontogenic, cartilaginous and connective tissue) derivatives. In amniotes, only cranial neural crest generates both classes, with trunk neural crest restricted to non-ectomesenchyme. By contrast, it has been suggested that anamniotes might generate derivatives of both classes at all axial levels, with trunk neural crest generating fin osteoblasts, scale mineral-forming cells and connective tissue cells; however, this has not been fully tested. The cause and evolutionary significance of this cranial/trunk dichotomy, and its absence in anamniotes, are debated. Recent experiments have disputed the contribution of fish trunk neural crest to fin osteoblasts and scale mineral-forming cells. This prompted us to test the contribution of anamniote trunk neural crest to fin connective tissue cells. Using genetics-based lineage tracing in zebrafish, we find that these fin mesenchyme cells derive entirely from the mesoderm and that neural crest makes no contribution. Furthermore, contrary to previous suggestions, larval fin mesenchyme cells do not generate the skeletogenic cells of the adult fin, but persist to form fibroblasts associated with adult fin rays. Our data demonstrate that zebrafish trunk neural crest does not generate ectomesenchymal derivatives and challenge long-held ideas about trunk neural crest fate. These findings have important implications for the ontogeny and evolution of the neural crest.

  8. Convergent Evolution of Head Crests in Two Domesticated Columbids Is Associated with Different Missense Mutations in EphB2.

    Science.gov (United States)

    Vickrey, Anna I; Domyan, Eric T; Horvath, Martin P; Shapiro, Michael D

    2015-10-01

    Head crests are important display structures in wild bird species and are also common in domesticated lineages. Many breeds of domestic rock pigeon (Columba livia) have crests of reversed occipital feathers, and this recessive trait is associated with a nonsynonymous coding mutation in the intracellular kinase domain of EphB2 (Ephrin receptor B2). The domestic ringneck dove (Streptopelia risoria) also has a recessive crested morph with reversed occipital feathers, and interspecific crosses between crested doves and pigeons produce crested offspring, suggesting a similar genetic basis for this trait in both species. We therefore investigated EphB2 as a candidate for the head crest phenotype of ringneck doves and identified a nonsynonymous coding mutation in the intracellular kinase domain that is significantly associated with the crested morph. This mutation is over 100 amino acid positions away from the crest mutation found in rock pigeons, yet both mutations are predicted to negatively affect the function of ATP-binding pocket. Furthermore, bacterial toxicity assays suggest that "crest" mutations in both species severely impact kinase activity. We conclude that head crests are associated with different mutations in the same functional domain of the same gene in two different columbid species, thereby representing striking evolutionary convergence in morphology and molecules. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Exploring the effects of working for endowments on behaviour in standard economic games.

    Directory of Open Access Journals (Sweden)

    Freya Harrison

    Full Text Available In recent years, significant advances have been made in understanding the adaptive (ultimate and mechanistic (proximate explanations for the evolution and maintenance of cooperation. Studies of cooperative behaviour in humans invariably use economic games. These games have provided important insights into the mechanisms that maintain economic and social cooperation in our species. However, they usually rely on the division of monetary tokens which are given to participants by the investigator. The extent to which behaviour in such games may reflect behaviour in the real world of biological markets--where money must be earned and behavioural strategies incur real costs and benefits--is unclear. To provide new data on the potential scale of this problem, we investigated whether people behaved differently in two standard economic games (public goods game and dictator game when they had to earn their monetary endowments through the completion of dull or physically demanding tasks, as compared with simply being given the endowment. The requirement for endowments to be 'earned' through labour did not affect behaviour in the dictator game. However, the requirement to complete a dull task reduced cooperation in the public goods game among the subset of participants who were not familiar with game theory. There has been some effort to test whether the conclusions drawn from standard, token-based cooperation games adequately reflect cooperative behaviour 'in the wild.' However, given the almost total reliance on such games to study cooperation, more exploration of this issue would be welcome. Our data are not unduly worrying, but they do suggest that further exploration is needed if we are to make general inferences about human behaviour from the results of structured economic games.

  10. 养老保险基金研究%A Study on Endowment Insurance Fund

    Institute of Scientific and Technical Information of China (English)

    刘文斌; 李乐乐; 宋超; 张道棋

    2012-01-01

    本文通过对我国基本养老保险中的“社会统筹”与“个人账户”中的有关数据进行了合理地分析和预测。在我国现行的养老保险制度的基础上,对1978年到2010年山东省职工的年平均工资用matlab进行了指数函数曲线拟合。预测出2011到2035年的年平均工资,从而预测出某企业在2000年-2034年的职工月工资和缴费指数。求出了各年龄段的替代率。计算了养老保险基金的缺口情况。通过lingo软件计算得出满足目标替代率和达到收支平衡时可采取的措施。%In this paper, relational data of society planing as a whole and individual account in Chinese basic endowment insurance are analyzed reasonably and forecasted. In Chinese current endowment insurance system, from 1978 to 2010, average wage of a year in ShanDong province are polyfited by matlab. We forecast average wage of a year from 2011 to 2035 and average wage of a month and paying index from 2000 to 2034 in a enterprise. Substituting probability of every age is solved. Insufficiency of endowment insurance fund is computed. Adopting measure of satisfying big substituting probability and achieving balance of income and outgo is computed by lingo.

  11. A Crucial Nexus: Literacy, Endowment and Public Consultation in Energy Decision Making

    Energy Technology Data Exchange (ETDEWEB)

    Bright, Steven

    2010-09-15

    Private and public organizations around the world are grappling with several challenging energy issues. In Canada, a recent poll showed that, despite the country's status as an energy exporter, citizens have mixed views on their energy literacy and influence over energy-related decision making. The energy endowment of Canada's varied regions partially explains these findings, but the overall picture is more complex. This research speaks to broader themes in the global energy dialogue such as the contributions of literacy to energy development, the role of public consultation in energy decision making and the value of money in motivating energy-efficiency behaviour.

  12. Skeletogenic fate of zebrafish cranial and trunk neural crest.

    Directory of Open Access Journals (Sweden)

    Erika Kague

    Full Text Available The neural crest (NC is a major contributor to the vertebrate craniofacial skeleton, detailed in model organisms through embryological and genetic approaches, most notably in chick and mouse. Despite many similarities between these rather distant species, there are also distinct differences in the contribution of the NC, particularly to the calvariae of the skull. Lack of information about other vertebrate groups precludes an understanding of the evolutionary significance of these differences. Study of zebrafish craniofacial development has contributed substantially to understanding of cartilage and bone formation in teleosts, but there is currently little information on NC contribution to the zebrafish skeleton. Here, we employ a two-transgene system based on Cre recombinase to genetically label NC in the zebrafish. We demonstrate NC contribution to cells in the cranial ganglia and peripheral nervous system known to be NC-derived, as well as to a subset of myocardial cells. The indelible labeling also enables us to determine NC contribution to late-forming bones, including the calvariae. We confirm suspected NC origin of cartilage and bones of the viscerocranium, including cartilages such as the hyosymplectic and its replacement bones (hymandibula and symplectic and membranous bones such as the opercle. The cleithrum develops at the border of NC and mesoderm, and as an ancestral component of the pectoral girdle was predicted to be a hybrid bone composed of both NC and mesoderm tissues. However, we find no evidence of a NC contribution to the cleithrum. Similarly, in the vault of the skull, the parietal bones and the caudal portion of the frontal bones show no evidence of NC contribution. We also determine a NC origin for caudal fin lepidotrichia; the presumption is that these are derived from trunk NC, demonstrating that these cells have the ability to form bone during normal vertebrate development.

  13. Enteric neural crest cells regulate vertebrate stomach patterning and differentiation.

    Science.gov (United States)

    Faure, Sandrine; McKey, Jennifer; Sagnol, Sébastien; de Santa Barbara, Pascal

    2015-01-15

    In vertebrates, the digestive tract develops from a uniform structure where reciprocal epithelial-mesenchymal interactions pattern this complex organ into regions with specific morphologies and functions. Concomitant with these early patterning events, the primitive GI tract is colonized by the vagal enteric neural crest cells (vENCCs), a population of cells that will give rise to the enteric nervous system (ENS), the intrinsic innervation of the GI tract. The influence of vENCCs on early patterning and differentiation of the GI tract has never been evaluated. In this study, we report that a crucial number of vENCCs is required for proper chick stomach development, patterning and differentiation. We show that reducing the number of vENCCs by performing vENCC ablations induces sustained activation of the BMP and Notch pathways in the stomach mesenchyme and impairs smooth muscle development. A reduction in vENCCs also leads to the transdifferentiation of the stomach into a stomach-intestinal mixed phenotype. In addition, sustained Notch signaling activity in the stomach mesenchyme phenocopies the defects observed in vENCC-ablated stomachs, indicating that inhibition of the Notch signaling pathway is essential for stomach patterning and differentiation. Finally, we report that a crucial number of vENCCs is also required for maintenance of stomach identity and differentiation through inhibition of the Notch signaling pathway. Altogether, our data reveal that, through the regulation of mesenchyme identity, vENCCs act as a new mediator in the mesenchymal-epithelial interactions that control stomach development. © 2015. Published by The Company of Biologists Ltd.

  14. Marek’s disease in the holland white crested chickens

    Directory of Open Access Journals (Sweden)

    Spalević Ljiljana

    2016-01-01

    Full Text Available Marek’s disease is a viral lymphoproliferative disease of poultry characterized by the creation of lymphoma in muscle, skin, eye or internal organs. Virus maturing into infective forms in follicular epithelium from where enters in the external environment where long time remains infectious. Poultry are infected by dust and remains the holder of the virus throughout their lives. The virus is transmitted vertically. The disease can occur in three forms: nervous, visceral and skin. Affected poultry may have any shape or combination of these. The aim of this study was to determine the cause of the disorder the health status in the flock of holland white crested chickens. Flock had 25 chickens whose ages ranged from 4-16 weeks. Observation, we noticed that the chickens are cachectic, showing signs of sporadic diarrhea and died 3 hens and 2 roosters. Pathoanatomical examination is ascertained changes in certain internal organs. The liver was enlarged with lymphoid proliferate on the surface and in the parenchyma, spleen increased several times and marbled, glandular stomach (proventriculus dilated with petechial hemorrhages on mucose. Changed organs was examination histopathological. In the liver were observed multifocal lymphoid infiltration with subsequent atrophy of the parenchyma, in addition to spleen lymphoid proliferation heterophyllus and histiocytic infiltrates, in proventriculus lymphoblastic infiltration with congestion of capillaries and small haemorrhages. In samples pathologically altered organs PCR method proved the genome of Marek’s disease virus serotype 1 . Based on these results we concluded that the livestock were sick from Marek’s disease, which is expressed in visceral form.

  15. Endothelial progenitor cells in cardiovascular diseases

    Institute of Scientific and Technical Information of China (English)

    Poay; Sian; Sabrina; Lee; Kian; Keong; Poh

    2014-01-01

    Endothelial dysfunction has been associated with the development of atherosclerosis and cardiovascular diseases. Adult endothelial progenitor cells(EPCs) are derived from hematopoietic stem cells and are capable of forming new blood vessels through a process of vas-culogenesis. There are studies which report correlations between circulating EPCs and cardiovascular risk fac-tors. There are also studies on how pharmacotherapies may influence levels of circulating EPCs. In this review, we discuss the potential role of endothelial progenitor cells as both diagnostic and prognostic biomarkers. In addition, we look at the interaction between cardio-vascular pharmacotherapies and endothelial progenitor cells. We also discuss how EPCs can be used directly and indirectly as a therapeutic agent. Finally, we evalu-ate the challenges facing EPC research and how these may be overcome.

  16. The Investigation of EM Scattering from the Time-Varying Overturning Wave Crest Model by the IEM

    Directory of Open Access Journals (Sweden)

    Xiao Meng

    2016-01-01

    Full Text Available Investigation of the electromagnetic (EM scattering of time-varying overturning wave crests is a worthwhile endeavor. Overturning wave crest is one of the reasons of sea spike generation, which increases the probability of false radar alarms and reduces the performance of multitarget detection in the environment. A three-dimensional (3D time-varying overturning wave crest model is presented in this paper; this 3D model is an improvement of the traditional two-dimensional (2D time-varying overturning wave crest model. The integral equation method (IEM was employed to investigate backward scattering radar cross sections (RCS at various incident angles of the 3D overturning wave crest model. The super phenomenon, where the intensity of horizontal polarization scattering is greater than that of vertical polarization scattering, is an important feature of sea spikes. Simulation results demonstrate that super phenomena may occur in some time samples as variations in the overturning wave crest.

  17. Core-Collapse supernovae and its progenitors

    CERN Document Server

    Bose, Subhash; Misra, Kuntal

    2016-01-01

    Massive stars unable to sustain gravitational collapse, at the end of nuclear burning stage, turns out into core-collapse supernovae, leaving behind compact objects like neutron stars or black holes. The progenitor properties like mass and metallicity primarily governs the explosion parameters and type of compact remnant. In this contribution we summarize observational study of three Core Collapse type IIP SNe 2012aw, 2013ab and 2013ej, which are rigorously observed from ARIES and other Indian observatories and discuss their progenitor and explosion properties.

  18. X Inactivation and Progenitor Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ruben Agrelo

    2011-04-01

    Full Text Available In mammals, silencing of one of the two X chromosomes is necessary to achieve dosage compensation. The 17 kb non-coding RNA called Xist triggers X inactivation. Gene silencing by Xist can only be achieved in certain contexts such as in cells of the early embryo and in certain hematopoietic progenitors where silencing factors are present. Moreover, these epigenetic contexts are maintained in cancer progenitors in which SATB1 has been identified as a factor related to Xist-mediated chromosome silencing.

  19. The endowment edifices of Nikola Spasic and his fund in Knez-Mihailova street

    Directory of Open Access Journals (Sweden)

    Borić Tijana

    2002-01-01

    Full Text Available Nikola Spasic (1838-1916, famous merchant and Serbian benefactor, gave a tremendous contribution to the architectural development of our recent past The area of Knez-Mihailova street preserves four magnificent edifices that Nikola Spasic bequeathed to the Serbian people, and those buildings are Spasic’s family house, the House of Serbian National Invalid Fund Saint George, Sloga palace and Grand passage. The plans for these buildings were drawn up by the most notable Serbian architects during the times of extreme scarcity and difficulties. Therefore, Spasic’s endowment edifices represent important testimony of the genesis of Serbian capital urban tissue. The creation of modern city and an uncritical hostile attitude toward the monuments of the epoch of academism, as well as the insufficiently researched field of our recent architectural past, have altogether made that many of valuable buildings have been destroyed or lost over the time. Because of carelessness and ignorance, Spasic’s endowment edifices sank into oblivion and reached us as neglected and of changed form. Nowadays, when the professional architectural revision of the role of the past is undertaken the researches of these important monuments, their evaluation and quality contribute to the creation of the proper critical judgment about our architecture.

  20. File list: Oth.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.20.AllAg.hESC_derived_neural_crests hg19 TFs and others Pluripotent stem ce...X1091550,SRX059360,SRX1091547,SRX059367,SRX059368 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.PSC.20.AllAg.hESC_derived_neural_crests.bed ... ...ll hESC derived neural crests SRX1091543,SRX1091542,SRX1091549,SRX1091551,SRX131914,SRX1091546,SRX1091541,SR

  1. File list: Oth.PSC.50.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.50.AllAg.hESC_derived_neural_crests hg19 TFs and others Pluripotent stem ce...X1091550,SRX059360,SRX1091547,SRX059367,SRX059368 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.PSC.50.AllAg.hESC_derived_neural_crests.bed ... ...ll hESC derived neural crests SRX1091543,SRX1091542,SRX1091549,SRX1091551,SRX131914,SRX1091546,SRX1091541,SR

  2. An exclusively mesodermal origin of fin mesenchyme demonstrates that zebrafish trunk neural crest does not generate ectomesenchyme

    OpenAIRE

    Lee, Raymond Teck Ho; Knapik, Ela W.; Thiery, Jean Paul; Carney, Thomas J.

    2013-01-01

    The neural crest is a multipotent stem cell population that arises from the dorsal aspect of the neural tube and generates both non-ectomesenchymal (melanocytes, peripheral neurons and glia) and ectomesenchymal (skeletogenic, odontogenic, cartilaginous and connective tissue) derivatives. In amniotes, only cranial neural crest generates both classes, with trunk neural crest restricted to non-ectomesenchyme. By contrast, it has been suggested that anamniotes might generate derivatives of both c...

  3. A new fossil dolphin Dilophodelphis fordycei provides insight into the evolution of supraorbital crests in Platanistoidea (Mammalia, Cetacea)

    Science.gov (United States)

    Boersma, Alexandra T.; McCurry, Matthew R.; Pyenson, Nicholas D.

    2017-05-01

    Many odontocete groups have developed enlarged facial crests, although these crests differ in topography, composition and function. The most elaborate crests occur in the South Asian river dolphin (Platanista gangetica), in which they rise dorsally as delicate, pneumatized wings anterior of the facial bones. Their position wrapping around the melon suggests their involvement in sound propagation for echolocation. To better understand the origin of crests in this lineage, we examined facial crests among fossil and living Platanistoidea, including a new taxon, Dilophodelphis fordycei, nov. gen. and sp., described herein, from the Early Miocene Astoria Formation of Oregon, USA. We measured the physical extent and thickness of platanistoid crests, categorized their relative position and used computed tomography scans to examine their internal morphology and relative bone density. Integrating these traits in a phylogenetic context, we determined that the onset of crest elaboration or enlargement and the evolution of crest pneumatization among the platanistoids were separate events, with crest enlargement beginning in the Oligocene. However, we find no evidence for pneumatization until possibly the Early Miocene, although certainly by the Middle Miocene. Such an evolutionary context, including data from the fossil record, should inform modelling efforts that seek to understand the diversity of sound generation morphology in Odontoceti.

  4. Corresponding mitochondrial DNA and niche divergence for crested newt candidate species.

    Directory of Open Access Journals (Sweden)

    Ben Wielstra

    Full Text Available Genetic divergence of mitochondrial DNA does not necessarily correspond to reproductive isolation. However, if mitochondrial DNA lineages occupy separate segments of environmental space, this supports the notion of their evolutionary independence. We explore niche differentiation among three candidate species of crested newt (characterized by distinct mitochondrial DNA lineages and interpret the results in the light of differences observed for recognized crested newt species. We quantify niche differences among all crested newt (candidate species and test hypotheses regarding niche evolution, employing two ordination techniques (PCA-env and ENFA. Niche equivalency is rejected: all (candidate species are found to occupy significantly different segments of environmental space. Furthermore, niche overlap values for the three candidate species are not significantly higher than those for the recognized species. As the three candidate crested newt species are, not only in terms of mitochondrial DNA genetic divergence, but also ecologically speaking, as diverged as the recognized crested newt species, our findings are in line with the hypothesis that they represent cryptic species. We address potential pitfalls of our methodology.

  5. Ancient evolutionary origin of vertebrate enteric neurons from trunk-derived neural crest.

    Science.gov (United States)

    Green, Stephen A; Uy, Benjamin R; Bronner, Marianne E

    2017-04-06

    The enteric nervous system of jawed vertebrates arises primarily from vagal neural crest cells that migrate to the foregut and subsequently colonize and innervate the entire gastrointestinal tract. Here we examine development of the enteric nervous system in the basal jawless vertebrate the sea lamprey (Petromyzon marinus) to gain insight into its evolutionary origin. Surprisingly, we find no evidence for the existence of a vagally derived enteric neural crest population in the lamprey. Rather, labelling with the lipophilic dye DiI shows that late-migrating cells, originating from the trunk neural tube and associated with nerve fibres, differentiate into neurons within the gut wall and typhlosole. We propose that these trunk-derived neural crest cells may be homologous to Schwann cell precursors, recently shown in mammalian embryos to populate post-embryonic parasympathetic ganglia, including enteric ganglia. Our results suggest that neural-crest-derived Schwann cell precursors made an important contribution to the ancient enteric nervous system of early jawless vertebrates, a role that was largely subsumed by vagal neural crest cells in early gnathostomes.

  6. Adenocarcinoma of the third portion of the duodenum in a man with CREST syndrome

    Directory of Open Access Journals (Sweden)

    Fragulidis Georgios

    2008-10-01

    Full Text Available Abstract Background CREST (Calcinosis, Raynaud's phenomenon, Esophageal dysmotility, Sclerodactyly and Telangiectasias syndrome has been rarely associated with other malignancies (lung, esophagus.This is the first report of a primary adenocarcinoma of the third portion of the duodenum in a patient with CREST syndrome. Case presentation A 54-year-old male patient with CREST syndrome presented with colicky postprandial pain of the upper abdomen, diminished food uptake and a 6-Kg-body weight loss during the previous 2 months. An ulcerative lesion in the third portion of the duodenum was revealed during duodenoscopy, with a diagnosis of adenocarcinoma on biopsy specimen histology. The patient underwent a partial pancreatoduodenectomy. No adjuvant therapy was instituted and follow-up is negative for local recurrence or metastases 21 months postoperatively. Conclusion CREST syndrome has been associated with colon cancer, gastric polyps, familial adenomatous polyposis (FAP syndrome and Crohn's disease; however, this is the first report of a primary adenocarcinoma of the duodenum in a patient with CREST syndrome. However, any etiologic relationship remains to be further investigated.

  7. cMyc Regulates the Size of the Premigratory Neural Crest Stem Cell Pool.

    Science.gov (United States)

    Kerosuo, Laura; Bronner, Marianne E

    2016-12-06

    The neural crest is a transient embryonic population that originates within the central nervous system (CNS) and then migrates into the periphery and differentiates into multiple cell types. The mechanisms that govern neural crest stem-like characteristics and self-renewal ability are poorly understood. Here, we show that the proto-oncogene cMyc is a critical factor in the chick dorsal neural tube, where it regulates the size of the premigratory neural crest stem cell pool. Loss of cMyc dramatically decreases the number of emigrating neural crest cells due to reduced self-renewal capacity, increased cell death, and shorter duration of the emigration process. Interestingly, rather than via E-Box binding, cMyc acts in the dorsal neural tube by interacting with another transcription factor, Miz1, to promote self-renewal. The finding that cMyc operates in a non-canonical manner in the premigratory neural crest highlights the importance of examining its role at specific time points and in an in vivo context.

  8. Assessing Donor Site Complications of Iliac Crest Bone Graft in Treatment of Scaphoid Nonunion

    Directory of Open Access Journals (Sweden)

    Davod Jafari

    2016-07-01

    Full Text Available Background Bone grafting is a common surgical technique to augment bone regeneration in orthopedic surgery. Autologous bone graft harvesting is the reliable treatment option and iliac crest is the most common harvesting site for healing bone fractures. However, the results of iliac crest bone graft harvesting are associated with morbidity and a number of complications. Objectives The aim of this study was to assess donor site complications of scaphoid nonunion, to find clinical outcomes and the impact of iliac crest bone graft on age, gender, pain, numbness, itching, nerve injury and scar appearance of patients. Methods In a prospective review of 61 cases of iliac crest bone graft procedures at the Shafa hospital from 2013 to 2014, complications including pain, infection, hematoma, stress fracture, hypertrophic scars, numbness area and itching were assessed clinically. Results Pain identified as the most common complication. The most common complications following postoperative pain at the donor site that reduced after six weeks were: numbness 3.27%, unsatisfactory scar appearance 3.27% and itching discomfort 1.63%. Conclusions Harvesting of iliac crest bone graft can be the ideal way to prepare graft procedures required surgery scaphoid nonunion fractures with minimal complications. Nevertheless, with an adequate preoperative planning and appropriate surgical technique, the prevalence of these complications can be reduced.

  9. Dissecting early regulatory relationships in the lamprey neural crest gene network.

    Science.gov (United States)

    Nikitina, Natalya; Sauka-Spengler, Tatjana; Bronner-Fraser, Marianne

    2008-12-23

    The neural crest, a multipotent embryonic cell type, originates at the border between neural and nonneural ectoderm. After neural tube closure, these cells undergo an epithelial-mesenchymal transition, migrate to precise, often distant locations, and differentiate into diverse derivatives. Analyses of expression and function of signaling and transcription factors in higher vertebrates has led to the proposal that a neural crest gene regulatory network (NC-GRN) orchestrates neural crest formation. Here, we interrogate the NC-GRN in the lamprey, taking advantage of its slow development and basal phylogenetic position to resolve early inductive events, 1 regulatory step at the time. To establish regulatory relationships at the neural plate border, we assess relative expression of 6 neural crest network genes and effects of individually perturbing each on the remaining 5. The results refine an upstream portion of the NC-GRN and reveal unexpected order and linkages therein; e.g., lamprey AP-2 appears to function early as a neural plate border rather than a neural crest specifier and in a pathway linked to MsxA but independent of ZicA. These findings provide an ancestral framework for performing comparative tests in higher vertebrates in which network linkages may be more difficult to resolve because of their rapid development.

  10. 新农保与城保的衔接路径——以河北省为倒%Joining Path between the New Rural Endowment Insurance and Urban Endowment Insurance

    Institute of Scientific and Technical Information of China (English)

    岳坤; 王晓亚

    2012-01-01

    以新农保与城保的衔接为出发点,分析了河北省社会养老保险制度衔接的障碍因素,提出以“个人账户”为其衔接点,并据此建立了新农保与城保制度衔接的模式和具体操作方案.%Starting from joining between new rural endowment insurance and urban endowment insurance, the restrained factors for social endowment insurance system joining in Hebei Province were analyzed. With individual account as joining point, the joining model and specific operation scheme were established.

  11. Characterization of hepatic progenitors from human fetal liver using CD34 as a hepatic progenitor marker

    Institute of Scientific and Technical Information of China (English)

    Parveen Nyamath; Ayesha AM; Aejaz Habeeb; Sanjeev Khosla; Aleem A Khan; CM Habibullah

    2007-01-01

    AIM: To enrich putative hepatic progenitors from the developing human fetal liver using CD34 as a marker.METHODS: Aborted fetuses of 13-20 wk were used for the isolation of liver cells. The cells were labeled with anti CD34; a marker used for isolating progenitor population and the cells were sorted using magnetic cell sorting. The positive fractions of cells were assessed for specific hepatic markers. Further, these cells were cultured in vitro for long term investigation.RESULTS: Flow cytometric and immunocytochemical analysis for alphafetoprotein (AFP) showed that the majority of the enriched CD34 positive cells were positive for AFP. Furthermore, these enriched cells proliferated in the long term and maintained hepatic characteristics in in vitro culture.CONCLUSION: The study shows that aborted human fetal liver is a potential source for isolation of hepatic progenitors for clinical applications. The study also demonstrates that CD34 can be a good marker for the enrichment of progenitor populations.

  12. Single Degenerate Progenitors of Type Ia Supernovae

    Science.gov (United States)

    Bours, Madelon; Toonen, Silvia; Nelemans, Gijs

    2013-01-01

    There is a general agreement that Type Ia supernovae correspond to the thermonuclear runaway of a white dwarf (WD) in a compact binary. The details of these progenitor systems are still unclear. Using the population synthesis code SeBa and several assumption for the WD retention efficiency, we estimate the delay times and supernova rates for the single degenerate scenario.

  13. Direct Conversion of Fibroblasts to Megakaryocyte Progenitors

    Directory of Open Access Journals (Sweden)

    Julian Pulecio

    2016-10-01

    Full Text Available Current sources of platelets for transfusion are insufficient and associated with risk of alloimmunization and blood-borne infection. These limitations could be addressed by the generation of autologous megakaryocytes (MKs derived in vitro from somatic cells with the ability to engraft and differentiate in vivo. Here, we show that overexpression of a defined set of six transcription factors efficiently converts mouse and human fibroblasts into MK-like progenitors. The transdifferentiated cells are CD41+, display polylobulated nuclei, have ploidies higher than 4N, form MK colonies, and give rise to platelets in vitro. Moreover, transplantation of MK-like murine progenitor cells into NSG mice results in successful engraftment and further maturation in vivo. Similar results are obtained using disease-corrected fibroblasts from Fanconi anemia patients. Our results combined demonstrate that functional MK progenitors with clinical potential can be obtained in vitro, circumventing the use of hematopoietic progenitors or pluripotent stem cells.

  14. Targeting human oligodendrocyte progenitors for myelin repair.

    Science.gov (United States)

    Dietz, Karen C; Polanco, Jessie J; Pol, Suyog U; Sim, Fraser J

    2016-09-01

    Oligodendrocyte development has been studied for several decades, and has served as a model system for both neurodevelopmental and stem/progenitor cell biology. Until recently, the vast majority of studies have been conducted in lower species, especially those focused on rodent development and remyelination. In humans, the process of myelination requires the generation of vastly more myelinating glia, occurring over a period of years rather than weeks. Furthermore, as evidenced by the presence of chronic demyelination in a variety of human neurologic diseases, it appears likely that the mechanisms that regulate development and become dysfunctional in disease may be, in key ways, divergent across species. Improvements in isolation techniques, applied to primary human neural and oligodendrocyte progenitors from both fetal and adult brain, as well as advancements in the derivation of defined progenitors from human pluripotent stem cells, have begun to reveal the extent of both species-conserved signaling pathways and potential key differences at cellular and molecular levels. In this article, we will review the commonalities and differences in myelin development between rodents and man, describing the approaches used to study human oligodendrocyte differentiation and myelination, as well as heterogeneity within targetable progenitor pools, and discuss the advances made in determining which conserved pathways may be both modeled in rodents and translate into viable therapeutic strategies to promote myelin repair.

  15. SUPERNOVA REMNANT PROGENITOR MASSES IN M31

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, Zachary G.; Williams, Benjamin F.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Fouesneau, Morgan; Weisz, Daniel R. [Department of Astronomy, University of Washington Seattle, Box 351580, WA 98195 (United States); Murphy, Jeremiah W. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Dolphin, Andrew E., E-mail: zachjenn@uw.edu, E-mail: adolphin@raytheon.com [Raytheon, 1151 East Hermans Road, Tucson, AZ 85706 (United States)

    2012-12-10

    Using Hubble Space Telescope photometry, we age-date 59 supernova remnants (SNRs) in the spiral galaxy M31 and use these ages to estimate zero-age main-sequence masses (M{sub ZAMS}) for their progenitors. To accomplish this, we create color-magnitude diagrams (CMDs) and employ CMD fitting to measure the recent star formation history of the regions surrounding cataloged SNR sites. We identify any young coeval population that likely produced the progenitor star, then assign an age and uncertainty to that population. Application of stellar evolution models allows us to infer the M{sub ZAMS} from this age. Because our technique is not contingent on identification or precise location of the progenitor star, it can be applied to the location of any known SNRs. We identify significant young star formation around 53 of the 59 SNRs and assign progenitor masses to these, representing a factor of {approx}2 increase over currently measured progenitor masses. We consider the remaining six SNRs as either probable Type Ia candidates or the result of core-collapse progenitors that have escaped their birth sites. In general, the distribution of recovered progenitor masses is bottom-heavy, showing a paucity of the most massive stars. If we assume a single power-law distribution, dN/dM{proportional_to}M{sup {alpha}}, then we find a distribution that is steeper than a Salpeter initial mass function (IMF) ({alpha} = -2.35). In particular, we find values of {alpha} outside the range -2.7 {>=} {alpha} {>=} -4.4 to be inconsistent with our measured distribution at 95% confidence. If instead we assume a distribution that follows a Salpeter IMF up to some maximum mass, then we find that values of M{sub Max} > 26 are inconsistent with the measured distribution at 95% confidence. In either scenario, the data suggest that some fraction of massive stars may not explode. The result is preliminary and requires more SNRs and further analysis. In addition, we use our distribution to estimate a

  16. Musculocontractural Ehlers–Danlos syndrome and neurocristopathies: dermatan sulfate is required for Xenopus neural crest cells to migrate and adhere to fibronectin

    Directory of Open Access Journals (Sweden)

    Nadège Gouignard

    2016-06-01

    Full Text Available Of all live births with congenital anomalies, approximately one-third exhibit deformities of the head and face. Most craniofacial disorders are associated with defects in a migratory stem and progenitor cell population, which is designated the neural crest (NC. Musculocontractural Ehlers–Danlos syndrome (MCEDS is a heritable connective tissue disorder with distinct craniofacial features; this syndrome comprises multiple congenital malformations that are caused by dysfunction of dermatan sulfate (DS biosynthetic enzymes, including DS epimerase-1 (DS-epi1; also known as DSE. Studies in mice have extended our understanding of DS-epi1 in connective tissue maintenance; however, its role in fetal development is not understood. We demonstrate that DS-epi1 is important for the generation of isolated iduronic acid residues in chondroitin sulfate (CS/DS proteoglycans in early Xenopus embryos. The knockdown of DS-epi1 does not affect the formation of early NC progenitors; however, it impairs the correct activation of transcription factors involved in the epithelial–mesenchymal transition (EMT and reduces the extent of NC cell migration, which leads to a decrease in NC-derived craniofacial skeleton, melanocytes and dorsal fin structures. Transplantation experiments demonstrate a tissue-autonomous role for DS-epi1 in cranial NC cell migration in vivo. Cranial NC explant and single-cell cultures indicate a requirement of DS-epi1 in cell adhesion, spreading and extension of polarized cell processes on fibronectin. Thus, our work indicates a functional link between DS and NC cell migration. We conclude that NC defects in the EMT and cell migration might account for the craniofacial anomalies and other congenital malformations in MCEDS, which might facilitate the diagnosis and development of therapies for this distressing condition. Moreover, the presented correlations between human DS-epi1 expression and gene sets of mesenchymal character, invasion and

  17. Age-related plasma chemistry findings in the buff-crested bustard (Eupodotis ruficrista gindiana).

    Science.gov (United States)

    Bailey, T A; Wernery, U; Howlett, J; Naldo, J; Samour, J H

    1998-12-01

    Blood samples were obtained from adult (> 1.5 years) and juvenile (2-8 weeks, 9-16 weeks and 17-24 weeks) captive buff-crested bustards (Eupodotis ruficrista gindiana) to study age-related changes. A total of twelve different tests were conducted using a Hitachi 90011 wet chemistry analyzer. A comparison of the values obtained was made between adult and juvenile buff-crested bustards and from the literature with other bustard species. Significant differences between adult and juvenile buff-crested bustards were found for glucose, uric acid, total protein, alkaline phosphatase, asparatate amino transferase and calcium. The results obtained from this study provide blood chemistry values for this species and demonstrate age-related differences between adult and juvenile birds.

  18. Radionuclide diagnosis and therapy of neural crest tumors using iodine-131 metaiodobenzylguanidine

    Energy Technology Data Exchange (ETDEWEB)

    Hoefnagel, C.A.; Voute, P.A.; de Kraker, J.; Marcuse, H.R.

    1987-03-01

    The successful application of (/sup 131/I)metaiodobenzylguanidine (MIBG) in diagnosis and therapy of pheochromocytoma has led to its use in other tumors which derive from the neural crest and potentially concentrate this radiopharmaceutical as well. In the present series, (/sup 131/)MIBG total-body scintigraphy was used for detection of neuroblastoma in 47 patients and 47 cases of other neural crest tumors. The method was found to be as reliable in neuroblastoma (sensitivity 95%, specificity 100%), as it is in pheochromocytoma. Although other neural crest tumors may concentrate (/sup 131/I)MIBG, this is not a consistent finding; however, it is useful to investigate which tumors do, as this may provide an alternative treatment modality for some patients. Although followup is still very short, preliminary results of therapeutic use of (/sup 131/I) MIBG in 21 patients indicate that this treatment modality may be effective in neuroblastoma and malignant pheochromocytoma.

  19. Solar Simulation for the CREST Preflight Thermal-Vacuum Test at B-2

    Science.gov (United States)

    Ziemke, Robert A.

    2013-01-01

    In June 2011, the multi-university sponsored Cosmic Ray Electron Synchrotron Telescope (CREST) has undergone thermal-vacuum qualification testing at the NASA Glenn Research Center (GRC), Plum Brook Station, Sandusky, Ohio. The testing was performed in the B- 2 Space Propulsion Facility vacuum chamber. The CREST was later flown over the Antarctic region as the payload of a stratospheric balloon. Solar simulation was provided by a system of planar infrared lamp arrays specifically designed for CREST. The lamp arrays, in conjunction with a liquid-nitrogen-cooled cryoshroud, achieved the required thermal conditions for the qualification tests. This report focuses on the design and analysis of the planar arrays based on first principles. Computational spreadsheets are included in the report.

  20. Short-crested waves in deep water: a numerical investigation of recent laboratory experiments

    DEFF Research Database (Denmark)

    Fuhrman, David R.; Madsen, Per A.

    2006-01-01

    A numerical study of quasi-steady, doubly-periodic monochromatic short-crested wave patterns in deep water is conducted using a high-order Boussinesq-type model. Simulations using linear wavemaker conditions in the nonlinear model are initially used to approximate conditions from recent laboratory...... experiments. The computed patterns share many features with those observed in wavetanks, including bending (both frontwards and backwards) of the wave crests, dipping at the crest centerlines, and a pronounced long modulation in the direction of propagation. A new and simple explanation for these features...... is provided, involving the release of spurious free first harmonics, due to the neglect of steady third-order components in the three-dimensional wave generation. A comparison with the experimentally observed beat length and amplitude matches the theoretical/numerical predictions well. Additionally, direct...

  1. Characterization of Hemagglutinin Negative Botulinum Progenitor Toxins

    Directory of Open Access Journals (Sweden)

    Suzanne R. Kalb

    2017-06-01

    Full Text Available Botulism is a disease involving intoxication with botulinum neurotoxins (BoNTs, toxic proteins produced by Clostridium botulinum and other clostridia. The 150 kDa neurotoxin is produced in conjunction with other proteins to form the botulinum progenitor toxin complex (PTC, alternating in size from 300 kDa to 500 kDa. These progenitor complexes can be classified into hemagglutinin positive or hemagglutinin negative, depending on the ability of some of the neurotoxin-associated proteins (NAPs to cause hemagglutination. The hemagglutinin positive progenitor toxin complex consists of BoNT, nontoxic non-hemagglutinin (NTNH, and three hemagglutinin proteins; HA-70, HA-33, and HA-17. Hemagglutinin negative progenitor toxin complexes contain BoNT and NTNH as the minimally functional PTC (M-PTC, but not the three hemagglutinin proteins. Interestingly, the genome of hemagglutinin negative progenitor toxin complexes comprises open reading frames (orfs which encode for three proteins, but the existence of these proteins has not yet been extensively demonstrated. In this work, we demonstrate that these three proteins exist and form part of the PTC for hemagglutinin negative complexes. Several hemagglutinin negative strains producing BoNT/A, /E, and /F were found to contain the three open reading frame proteins. Additionally, several BoNT/A-containing bivalent strains were examined, and NAPs from both genes, including the open reading frame proteins, were associated with BoNT/A. The open reading frame encoded proteins are more easily removed from the botulinum complex than the hemagglutinin proteins, but are present in several BoNT/A and /F toxin preparations. These are not easily removed from the BoNT/E complex, however, and are present even in commercially-available purified BoNT/E complex.

  2. Evolution of neural crest and placodes: amphioxus as a model for the ancestral vertebrate?

    Science.gov (United States)

    Holland, L. Z.; Holland, N. D.

    2001-01-01

    Recent studies of protochordates (ascidian tunicates and amphioxus) have given insights into possible ancestors of 2 of the characteristic features of the vertebrate head: neural crest and placodes. The neural crest probably evolved from cells on either side of the neural plate-epidermis boundary in a protochordate ancestral to the vertebrates. In amphioxus, homologues of several vertebrate neural crest marker genes (BMP2/4, Pax3/7, Msx, Dll and Snail) are expressed at the edges of the neural plate and/or adjacent nonneural ectoderm. Some of these markers are also similarly expressed in tunicates. In protochordates, however, these cells, unlike vertebrate neural crest, neither migrate as individuals through embryonic tissues nor differentiate into a wide spectrum of cell types. Therefore, while the protochordate ancestor of the vertebrates probably had the beginnings of a genetic programme for neural crest formation, this programme was augmented in the earliest vertebrates to attain definitive neural crest. Clear homologues of vertebrate placodes are lacking in protochordates. However, both amphioxus and tunicates have ectodermal sensory cells. In tunicates these are all primary neurons, sending axons to the central nervous system, while in amphioxus, the ectodermal sensory cells include both primary neurons and secondary neurons lacking axons. Comparisons of developmental gene expression suggest that the anterior ectoderm in amphioxus may be homologous to the vertebrate olfactory placode, the only vertebrate placode with primary, not secondary, neurons. Similarly, biochemical, morphological and gene expression data suggest that amphioxus and tunicates also have homologues of the adenohypophysis, one of the few vertebrate structures derived from nonneurogenic placodes. In contrast, the origin of the other vertebrate placodes is very uncertain.

  3. Neural crest stem cell population in craniomaxillofacial development and tissue repair

    Directory of Open Access Journals (Sweden)

    M La Noce

    2014-10-01

    Full Text Available Neural crest cells, delaminating from the neural tube during migration, undergo an epithelial-mesenchymal transition and differentiate into several cell types strongly reinforcing the mesoderm of the craniofacial body area – giving rise to bone, cartilage and other tissues and cells of this human body area. Recent studies on craniomaxillofacial neural crest-derived cells have provided evidence for the tremendous plasticity of these cells. Actually, neural crest cells can respond and adapt to the environment in which they migrate and the cranial mesoderm plays an important role toward patterning the identity of the migrating neural crest cells. In our experience, neural crest-derived stem cells, such as dental pulp stem cells, can actively proliferate, repair bone and give rise to other tissues and cytotypes, including blood vessels, smooth muscle, adipocytes and melanocytes, highlighting that their use in tissue engineering is successful. In this review, we provide an overview of the main pathways involved in neural crest formation, delamination, migration and differentiation; and, in particular, we concentrate our attention on the translatability of the latest scientific progress. Here we try to suggest new ideas and strategies that are needed to fully develop the clinical use of these cells. This effort should involve both researchers/clinicians and improvements in good manufacturing practice procedures. It is important to address studies towards clinical application or take into consideration that studies must have an effective therapeutic prospect for humans. New approaches and ideas must be concentrated also toward stem cell recruitment and activation within the human body, overcoming the classical grafting.

  4. Evolution of neural crest and placodes: amphioxus as a model for the ancestral vertebrate?

    Science.gov (United States)

    Holland, L. Z.; Holland, N. D.

    2001-01-01

    Recent studies of protochordates (ascidian tunicates and amphioxus) have given insights into possible ancestors of 2 of the characteristic features of the vertebrate head: neural crest and placodes. The neural crest probably evolved from cells on either side of the neural plate-epidermis boundary in a protochordate ancestral to the vertebrates. In amphioxus, homologues of several vertebrate neural crest marker genes (BMP2/4, Pax3/7, Msx, Dll and Snail) are expressed at the edges of the neural plate and/or adjacent nonneural ectoderm. Some of these markers are also similarly expressed in tunicates. In protochordates, however, these cells, unlike vertebrate neural crest, neither migrate as individuals through embryonic tissues nor differentiate into a wide spectrum of cell types. Therefore, while the protochordate ancestor of the vertebrates probably had the beginnings of a genetic programme for neural crest formation, this programme was augmented in the earliest vertebrates to attain definitive neural crest. Clear homologues of vertebrate placodes are lacking in protochordates. However, both amphioxus and tunicates have ectodermal sensory cells. In tunicates these are all primary neurons, sending axons to the central nervous system, while in amphioxus, the ectodermal sensory cells include both primary neurons and secondary neurons lacking axons. Comparisons of developmental gene expression suggest that the anterior ectoderm in amphioxus may be homologous to the vertebrate olfactory placode, the only vertebrate placode with primary, not secondary, neurons. Similarly, biochemical, morphological and gene expression data suggest that amphioxus and tunicates also have homologues of the adenohypophysis, one of the few vertebrate structures derived from nonneurogenic placodes. In contrast, the origin of the other vertebrate placodes is very uncertain.

  5. Final report for the endowment of simulator agents with human-like episodic memory LDRD.

    Energy Technology Data Exchange (ETDEWEB)

    Speed, Ann Elizabeth; Lippitt, Carl Edward; Thomas, Edward Victor; Xavier, Patrick Gordon; Forsythe, Christi A.; Schaller, Mark J.; Schoenwald, David Alan

    2003-12-01

    This report documents work undertaken to endow the cognitive framework currently under development at Sandia National Laboratories with a human-like memory for specific life episodes. Capabilities have been demonstrated within the context of three separate problem areas. The first year of the project developed a capability whereby simulated robots were able to utilize a record of shared experience to perform surveillance of a building to detect a source of smoke. The second year focused on simulations of social interactions providing a queriable record of interactions such that a time series of events could be constructed and reconstructed. The third year addressed tools to promote desktop productivity, creating a capability to query episodic logs in real time allowing the model of a user to build on itself based on observations of the user's behavior.

  6. Quinoxaline 1,4-dioxide: a versatile scaffold endowed with manifold activities.

    Science.gov (United States)

    Carta, A; Corona, P; Loriga, M

    2005-01-01

    Since 1940s, Quinoxaline 1,4-dioxides (QdNO's) are known as potent antibacterial agents, and subtherapeutic levels have been used to promote growth and improve efficiency of feed conversion in animal feed. They have also shown a selective cytotoxicity against hypoxic cells present in solid tumours. Furthermore, recent studies have put in evidence that QdNO's are endowed with antitubercular, antiprotozoal and anticandida activities. On the other hand, several authors have reported about photoallergic and mutagenic effects of some derivatives. QdNO's may also cause the development of antibiotic-resistant bacteria and influence the horizontal transfer of virulence genes between bacteria. In this review article we report the biological properties, the mode of action and Structure Activity Relationship (SAR) studies of the QdNO derivatives. Furthermore, some cytogenetic and genotoxic effects, classical and more recent method of synthesis, the quinoxaline 1,4-dioxides, and some of their most important reactions, were also reported.

  7. WhiteDwarf.org - Establishing a permanent endowment for the Whole Earth Telescope

    CERN Document Server

    Metcalfe, T S

    2002-01-01

    White Dwarf Research Corporation is a 501(c)(3) non-profit organization dedicated to scientific research and public education on topics relevant to white dwarf stars. It was founded in 1999 in Austin, Texas to help fulfill the need for an alternative research center where scarce funding dollars could be used more efficiently, and to provide a direct link between astronomers who study white dwarf stars and the general public. Due to its administrative simplicity, WDRC can facilitate the funding of multi-institutional and international collaborations, provide seamless grant portability, minimize overhead rates, and actively seek non-governmental funding sources. I describe the motivation for, and current status of, one of the long-term goals of WDRC: to establish a permanent endowment for the operation of the Whole Earth Telescope. I pay particular attention to fund-raising efforts through the website at http://WhiteDwarf.org/donate/

  8. Pseudo-Reimannian manifolds endowed with an almost para f-structure

    Directory of Open Access Journals (Sweden)

    Vladislav V. Goldberg

    1985-01-01

    Full Text Available Let M˜(U,Ω˜,η˜,ξ,g˜ be a pseudo-Riemannian manifold of signature (n+1,n. One defines on M˜ an almost cosymplectic para f-structure and proves that a manifold M˜ endowed with such a structure is ξ-Ricci flat and is foliated by minimal hypersurfaces normal to ξ, which are of Otsuki's type. Further one considers on M˜ a 2(n−1-dimensional involutive distribution P⊥ and a recurrent vector field V˜. It is proved that the maximal integral manifold M⊥ of P⊥ has V as the mean curvature vector (up to 1/2(n−1. If the complimentary orthogonal distribution P of P⊥ is also involutive, then the whole manifold M˜ is foliate. Different other properties regarding the vector field V˜ are discussed.

  9. New 1,4-dihydropyridines endowed with NO-donor and calcium channel agonist properties.

    Science.gov (United States)

    Visentin, Sonja; Rolando, Barbara; Di Stilo, Antonella; Fruttero, Roberta; Novara, Monica; Carbone, Emilio; Roussel, Christian; Vanthuyne, Nicolas; Gasco, Alberto

    2004-05-06

    A new series of calcium channel agonists structurally related to Bay K8644, containing NO donor furoxans and the related furazans unable to release NO, is described. The racemic mixtures were studied for their action on L-type Ca(2+) channels expressed in cultured rat insulinoma RINm5F cells. All the products proved to be potent calcium channel agonists. All the racemic mixtures, with the only exception of the carbamoyl derivatives 9, 12 endowed with scanty solubility, were separated by chiral chromatography into the corresponding enantiomers; the (+) enantiomers were found to be potent agonists while the (-) ones were feeble antagonists. The racemic mixtures were also assessed for their positive inotropic activity on electrically stimulated rat papillary muscle and for their ability to increase Ca(2+) entry into the vascular smooth muscle of rat aorta strips. The cyanofuroxan 8 proved to be an interesting product with dual Ca(2+)-dependent positive inotropic and NO-dependent vasodilating activity.

  10. Conditional short-crested waves in shallow water and with superimposed current

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2002-01-01

    For bottom-supported offshore structures like oil drilling rigs and oil production platforms, a deterministic design wave approach is often applied using a regular non-linear Stokes´ wave. Thereby, the procedure accounts for non-linear effects in the wave loading but the randomness of the ocean...... wave, given the value of the wave crest at a specific point in time or space. In the present paper a derivation of the expected linear short-crested wave riding on a uniform current is given. The analysis is based on the conventional shallow water Airy wave theory and the direction of the main wind...

  11. Conditional Second Order Short-crested Water Waves Applied to Extreme Wave Episodes

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2005-01-01

    A derivation of the mean second order short-crested wave pattern and associated wave kinematics, conditional on a given magnitude of the wave crest, is presented. The analysis is based on the second order Sharma and Dean finite water wave theory. A comparison with a measured extreme wave profile......, the Draupner New Year Wave, shows a good agreement in the mean, indicating that this second order wave can be a good identifier of the shape and occurrence of extreme wave events. A discussion on its use as an initial condition for a fully non-linear three-dimensional surface wave analysis is given....

  12. Density of bunches of native bluebunch wheatgrass and alien crested wheatgrass

    Energy Technology Data Exchange (ETDEWEB)

    Rickard, W.H.

    1985-10-01

    The density of bunches of bluebunch wheatgrass in a natural undisturbed stand averaged 3.28 per m/sup 2/ as compared to 2.96 per m/sup 2/ for a nearby stand of crested wheatgrass that was planted 30 years ago. Bunch density was similar in both stands indicating that spacing is a response to an environment deficient in soil water. Bunches of crested wheatgrass on the average weighed 3.5 times more than bunches of bluebunch wheatgrass and they also produced a greater weight of seedheads.

  13. Nuchal crest avulsion fracture in 2 horses : a cause of headshaking : clinical communication

    Directory of Open Access Journals (Sweden)

    A. Voigt

    2009-05-01

    Full Text Available The medical records of 2 Thoroughbred horses that developed headshaking after blunt trauma to the occipital region are reviewed. The history, signalment, clinical signs, diagnostic methods, diagnosis and treatment were recorded in each case. Both horses displayed headshaking, while one horse repeatedly lifted its upper lip and pawed excessively at the ground. In both horses, diagnostic imaging of the occipital region revealed avulsion fragments of the nuchal crest and a nuchal desmitis in association with hyperfibrinogenaemia. The presence of an avulsion fragment of the nuchal crest with associated nuchal desmitis should be considered in horses presenting with headshaking and may respond favourably to conservative therapy.

  14. Analysis of Normal Hematopoietic Stem and Progenitor Cell Contents in Childhood Acute Leukemia Bone Marrow.

    Science.gov (United States)

    Balandrán, Juan Carlos; Vadillo, Eduardo; Dozal, David; Reyes-López, Alfonso; Sandoval-Cabrera, Antonio; Laffont-Ortiz, Merle Denisse; Prieto-Chávez, Jessica L; Vilchis-Ordoñez, Armando; Quintela-Nuñez Del Prado, Henry; Mayani, Héctor; Núñez-Enríquez, Juan Carlos; Mejía-Aranguré, Juan Manuel; López-Martínez, Briceida; Jiménez-Hernández, Elva; Pelayo, Rosana

    2016-11-01

    Childhood acute leukemias (AL) are characterized by the excessive production of malignant precursor cells at the expense of effective blood cell development. The dominance of leukemic cells over normal progenitors may result in either direct suppression of functional hematopoiesis or remodeling of microenvironmental niches, contributing to BM failure and AL-associated mortality. We undertook this study to investigate the contents and functional activity of hematopoietic stem/progenitor cells (HSPC) and their relationship to immune cell production and risk status in AL pediatric patients. Multiparametric flow cytometry of BM aspirates was performed to classify AL on the basis of lineage and differentiation stages and to analyze HSPC and immune cell frequencies. Controlled co-culture systems were conducted to evaluate functional lineage potentials of primitive cells. Statistical correlations and inter-group significant differences were established. Among 113 AL BM aspirates, 26.5% corresponded to ProB, 19.5% to PreB and 32% contain ProB and PreB differentiation stages, whereas nearly 9% of the cases were T- and 13% myeloid-lineage leukemias. We identified ProB-ALL as the subtype endowed with the highest relative contents of HSPC, whereas T-ALL and PreB-ALL showed a critically reduced size of both HSC and MLP compartments. Notably, lower cell frequencies of HSPC in ProB-ALL correlated to high-risk prognosis at disease debut. HSPC abundance at initial diagnosis may aid to predict the clinical course of ALL and to identify high-risk patients. A clearer understanding of their population dynamics and functional properties in the leukemia setting will potentially pave the way for targeted therapies. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

  15. File list: ALL.PSC.05.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  16. 76 FR 30757 - Endangered and Threatened Wildlife and Plants; Listing the Salmon-Crested Cockatoo as Threatened...

    Science.gov (United States)

    2011-05-26

    ... and Plant Health Inspection Service requires veterinary health certificates and health inspections for... salmon-crested cockatoo is endemic to the island of Seram (alternate spelling, Ceram), with records from...; Isherwood et al. 1998, p. 18). For a listing of specific distribution records of the salmon-crested...

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    Lifescience Database Archive (English)

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  4. Incisional Colopexy for Treatment of Chronic, Recurrent Colocloacal Prolapse in a Sulphur-Crested Cockatoo (Cacatua galerita)

    NARCIS (Netherlands)

    van Zeeland, Yvonne; Schoemaker, Nico; van Sluijs, Freek

    2014-01-01

    Objective To report a surgical technique for treatment of chronic, recurrent cloacal prolapse in a sulphur-crested cockatoo (Cacatua galerita). Study Design Clinical report Animals Sulphur-crested cockatoo (n = 1) Methods The bird was admitted with a 2-year history of periodic lethargy, decreased ap

  5. Telangiectasis in CREST syndrome and systemic sclerosis: correlation of clinical and pathological features with response to pulsed dye laser treatment.

    Science.gov (United States)

    Halachmi, Shlomit; Gabari, Osama; Cohen, Sarit; Koren, Romelia; Amitai, Dan Ben; Lapidoth, Moshe

    2014-01-01

    Telangiectasia are cardinal features of systemic sclerosis (SS) and calcinosis, Raynaud's syndrome, esophageal motility, sclerodactyly, telangiectasias (CREST) syndrome. The etiology of telangiectasia in these syndromes is unknown, but vascular dysfunction has been proposed. However, the telangiectasia of CREST have anecdotally been considered relatively resistant to pulse dye laser (PDL), the treatment of choice for classic telangiectasia. The study was designed to test whether SS/CREST telangiectasia require more treatments than sporadic telangiectasia and to identify clinical and histological features that could explain such an effect. Nineteen skin biopsies from patients with SS or CREST and 10 control biopsies were examined and compared for features that may predict a differential response to PDL. Sixteen cases of SS or CREST treated with PDL between 1997 and 2007 were evaluated and response to treatment was compared with 20 patients with sporadic telangiectasis. Relative to normal skin, CREST/scleroderma telangiectasia exhibited thickened vessels in 17 out of 19 sections and thickened collagen fibers in the reticular or deep dermis in all sections. The number of treatments required to clear SS/CREST telangiectasia was approximately twofold higher. SS/CREST telangiectasia are more resistant to PDL but can be effectively cleared with more treatments.

  6. File list: His.PSC.20.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.20.AllAg.hESC_derived_neural_crests hg19 Histone Pluripotent stem cell hESC derived neu...30,SRX059362,SRX1091539,SRX059364 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.20.AllAg.hESC_derived_neural_crests.bed ...

  7. File list: His.PSC.10.AllAg.hESC_derived_neural_crests [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.10.AllAg.hESC_derived_neural_crests hg19 Histone Pluripotent stem cell hESC derived neu...3,SRX1091531,SRX059364,SRX1091530 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.10.AllAg.hESC_derived_neural_crests.bed ...

  8. Derivation of myoepithelial progenitor cells from bipotent mammary stem/progenitor cells.

    Directory of Open Access Journals (Sweden)

    Xiangshan Zhao

    Full Text Available There is increasing evidence that breast and other cancers originate from and are maintained by a small fraction of stem/progenitor cells with self-renewal properties. Recent molecular profiling has identified six major subtypes of breast cancer: basal-like, ErbB2-overexpressing, normal breast epithelial-like, luminal A and B, and claudin-low subtypes. To help understand the relationship among mammary stem/progenitor cells and breast cancer subtypes, we have recently derived distinct hTERT-immortalized human mammary stem/progenitor cell lines: a K5(+/K19(- type, and a K5(+/K19(+ type. Under specific culture conditions, bipotent K5(+/K19(- stem/progenitor cells differentiated into stable clonal populations that were K5(-/K19(- and exhibit self-renewal and unipotent myoepithelial differentiation potential in contrast to the parental K5(+/K19(- cells which are bipotent. These K5(-/K19(- cells function as myoepithelial progenitor cells and constitutively express markers of an epithelial to mesenchymal transition (EMT and show high invasive and migratory abilities. In addition, these cells express a microarray signature of claudin-low breast cancers. The EMT characteristics of an un-transformed unipotent mammary myoepithelial progenitor cells together with claudin-low signature suggests that the claudin-low breast cancer subtype may arise from myoepithelial lineage committed progenitors. Availability of immortal MPCs should allow a more definitive analysis of their potential to give rise to claudin-low breast cancer subtype and facilitate biological and molecular/biochemical studies of this disease.

  9. A Native Arbuscular Mycorrhizal Fungus, Acaulospora scrobiculata Stimulated Growth of Mongolian Crested Wheatgrass ( Agropyron cristatum (L. Gaertn.

    Directory of Open Access Journals (Sweden)

    Burenjargal Otgonsuren

    2010-12-01

    Full Text Available Agr opyron cristatum (L. Gaertn. (crested wheatgrass is an endemic plant species, which dominates most area of the Mongolian steppe and forest steppe. In the present study, spores of arbuscular mycorrhizal fungi in the rhizosphere soil of crested wheatgrass were isolated with wet- sieving/decanting methods, and the major species was identifi ed as Acaulospora scrobiculata Trappe. For arbuscular-mycorrhizal resynthesis, the spores of A. scrobiculata were propagated with corn pot-culture technique and inoculated onto the roots of crested wheatgrass seedlings. The inoculated crested wheatgrass seedlings exhibited vigor in growth, and examination of the root structure revealed the occurrence of arbuscules and vesicles in the cortical cells. These results demonstrated that A. scrobiculata could effectively form arbuscular mycorrhizas with crested wheatgrass and promote its growth, which can be used to restore Mongolian grassland.

  10. On the progenitor of V838 Monocerotis

    CERN Document Server

    Tylenda, R; Szczerba, R

    2004-01-01

    We summarize and analyze the available observational data on the progenitor and the enviroment of V838 Mon, the object that erupted in January 2002. We show that the radio and infrared observed matter in the vicinity of V838 Mon could not have its origin in mass loss from V838 Mon but is of interstellar origin. Also from the light echo evolution we conclude that the reflecting dust is of the same nature and not blown by V838 Mon in the past. This is compatible with the photometric data for the progenitor of V838 Mon, from which we exclude the possibility that the object before eruption was an evolved red giant star (AGB or RGB star). We find that most likely it was a main sequence star of \\~5-10 M_sun.

  11. Interneuron progenitor transplantation to treat CNS dysfunction

    Directory of Open Access Journals (Sweden)

    Muhammad O Chohan

    2016-08-01

    Full Text Available Due to the inadequacy of endogenous repair mechanisms diseases of the nervous system remain a major challenge to scientists and clinicians. Stem cell based therapy is an exciting and viable strategy that has been shown to ameliorate or even reverse symptoms of CNS dysfunction in preclinical animal models. Of particular importance has been the use of GABAergic interneuron progenitors as a therapeutic strategy. Born in the neurogenic niches of the ventral telencephalon, interneuron progenitors retain their unique capacity to disperse, integrate and induce plasticity in adult host circuitries following transplantation. Here we discuss the potential of interneuron based transplantation strategies as it relates to CNS disease therapeutics. We also discuss mechanisms underlying their therapeutic efficacy and some of the challenges that face the field.

  12. Resident mesenchymal progenitors of articular cartilage.

    Science.gov (United States)

    Candela, Maria Elena; Yasuhara, Rika; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi

    2014-10-01

    Articular cartilage has poor capacity of self-renewal and repair. Insufficient number and activity of resident mesenchymal (connective tissue) progenitors is likely one of the underlying reasons. Chondroprogenitors reside not only in the superficial zone of articular cartilage but also in other zones of articular cartilage and in the neighboring tissues, including perichondrium (groove of Ranvier), synovium and fat pad. These cells may respond to injury and contribute to articular cartilage healing. In addition, marrow stromal cells can migrate through subchondral bone when articular cartilage is damaged. We should develop drugs and methods that correctly stimulate resident progenitors for improvement of repair and inhibition of degenerative changes in articular cartilage. Copyright © 2014. Published by Elsevier B.V.

  13. Noninvasive Imaging of Administered Progenitor Cells

    Energy Technology Data Exchange (ETDEWEB)

    Steven R Bergmann, M.D., Ph.D.

    2012-12-03

    The objective of this research grant was to develop an approach for labeling progenitor cells, specifically those that we had identified as being able to replace ischemic heart cells, so that the distribution could be followed non-invasively. In addition, the research was aimed at determining whether administration of progenitor cells resulted in improved myocardial perfusion and function. The efficiency and toxicity of radiolabeling of progenitor cells was to be evaluated. For the proposed clinical protocol, subjects with end-stage ischemic coronary artery disease were to undergo a screening cardiac positron emission tomography (PET) scan using N-13 ammonia to delineate myocardial perfusion and function. If they qualified based on their PET scan, they would undergo an in-hospital protocol whereby CD34+ cells were stimulated by the administration of granulocytes-colony stimulating factor (G-CSF). CD34+ cells would then be isolated by apharesis, and labeled with indium-111 oxine. Cells were to be re-infused and subjects were to undergo single photon emission computed tomography (SPECT) scanning to evaluate uptake and distribution of labeled progenitor cells. Three months after administration of progenitor cells, a cardiac PET scan was to be repeated to evaluate changes in myocardial perfusion and/or function. Indium oxine is a radiopharmaceutical for labeling of autologous lymphocytes. Indium-111 (In-111) decays by electron capture with a t{sub ½} of 67.2 hours (2.8 days). Indium forms a saturated complex that is neutral, lipid soluble, and permeates the cell membrane. Within the cell, the indium-oxyquinolone complex labels via indium intracellular chelation. Following leukocyte labeling, ~77% of the In-111 is incorporated in the cell pellet. The presence of red cells and /or plasma reduces the labeling efficacy. Therefore, the product needed to be washed to eliminate plasma proteins. This repeated washing can damage cells. The CD34 selected product was a 90

  14. The endocannabinoid system drives neural progenitor proliferation.

    Science.gov (United States)

    Aguado, Tania; Monory, Krisztina; Palazuelos, Javier; Stella, Nephi; Cravatt, Benjamin; Lutz, Beat; Marsicano, Giovanni; Kokaia, Zaal; Guzmán, Manuel; Galve-Roperh, Ismael

    2005-10-01

    The discovery of multipotent neural progenitor (NP) cells has provided strong support for the existence of neurogenesis in the adult brain. However, the signals controlling NP proliferation remain elusive. Endocannabinoids, the endogenous counterparts of marijuana-derived cannabinoids, act as neuromodulators via presynaptic CB1 receptors and also control neural cell death and survival. Here we show that progenitor cells express a functional endocannabinoid system that actively regulates cell proliferation both in vitro and in vivo. Specifically, NPs produce endocannabinoids and express the CB1 receptor and the endocannabinoid-inactivating enzyme fatty acid amide hydrolase (FAAH). CB1 receptor activation promotes cell proliferation and neurosphere generation, an action that is abrogated in CB1-deficient NPs. Accordingly, proliferation of hippocampal NPs is increased in FAAH-deficient mice. Our results demonstrate that endocannabinoids constitute a new group of signaling cues that regulate NP proliferation and thus open novel therapeutic avenues for manipulation of NP cell fate in the adult brain.

  15. 76 FR 63665 - National Endowment for the Arts; President's Committee on the Arts and the Humanities: Meeting #67

    Science.gov (United States)

    2011-10-13

    ...] [FR Doc No: 2011-26424] NATIONAL FOUNDATION ON THE ARTS AND THE HUMANITIES National Endowment for the Arts; President's Committee on the Arts and the Humanities: Meeting 67 Pursuant to Section 10(a)(2) of... of the President's Committee on the Arts and the Humanities (PCAH) will be held on Tuesday,...

  16. 75 FR 13312 - National Endowment for the Arts; National Council on the Arts 169th Meeting-Addendum

    Science.gov (United States)

    2010-03-19

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; National Council on the Arts 169th Meeting...) regarding the 169th meeting of the National Council on the Arts. A portion of this meeting, from 9 a.m. to... accessed by going to Art Works blog at http://www.arts.gov/artworks . If, in the course of the open...

  17. 75 FR 52857 - National Endowment for the Humanities Implementation of OMB Guidance on Drug-Free Workplace...

    Science.gov (United States)

    2010-08-30

    ... make no substantive change in NEH's policy or procedures for drug-free workplace. DATES: This final... any unintended changes this action makes in NEH policies and procedures for drug-free workplace. All... Implementation of OMB Guidance on Drug-Free Workplace Requirements AGENCY: National Endowment for the Humanities...

  18. A Comparison of ICT Knowledge and Usage among Female Distance Learners in Endowed and Deprived Communities of a Developing Country

    Science.gov (United States)

    Kwapong, Olivia Adwoa Tiwaah Frimpong

    2009-01-01

    Working with the premise that information and communications technology (ICT) has the capacity to make or unmake so far as women's empowerment is concerned, this article looks at the ICT situation among female distance learners in both endowed and under-served parts of Ghana, to check the user differentials among the two contrasting groups through…

  19. Endothelial progenitor cell biology in ankylosing spondylitis.

    Science.gov (United States)

    Verma, Inderjeet; Syngle, Ashit; Krishan, Pawan

    2015-03-01

    Endothelial progenitor cells (EPCs) are unique populations which have reparative potential in overcoming endothelial damage and reducing cardiovascular risk. Patients with ankylosing spondylitis (AS) have increased risk of cardiovascular morbidity and mortality. The aim of this study was to investigate the endothelial progenitor cell population in AS patients and its potential relationships with disease variables. Endothelial progenitor cells were measured in peripheral blood samples from 20 AS and 20 healthy controls by flow cytometry on the basis of CD34 and CD133 expression. Disease activity was evaluated by using Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Functional ability was monitored by using Bath Ankylosing Spondylitis Functional Index (BASFI). EPCs were depleted in AS patients as compared to healthy controls (CD34(+) /CD133(+) : 0.027 ± 0.010% vs. 0.044 ± 0.011%, P < 0.001). EPC depletions were significantly associated with disease duration (r = -0.52, P = 0.01), BASDAI (r = -0.45, P = 0.04) and C-reactive protein (r = -0.5, P = 0.01). This is the first study to demonstrate endothelial progenitor cell depletion in AS patients. EPC depletions inversely correlate with disease duration, disease activity and inflammation, suggesting the pivotal role of inflammation in depletion of EPCs. EPC would possibly also serve as a therapeutic target for preventing cardiovascular disease in AS. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  20. 77 FR 40374 - Proposed Information Collection; Depredation Orders for Double-Crested Cormorants

    Science.gov (United States)

    2012-07-09

    ... Fish and Wildlife Service Proposed Information Collection; Depredation Orders for Double- Crested... Depredation Order) authorize aquaculture producers and the U.S. Department of Agriculture (APHIS-Wildlife... commit depredations on commercial freshwater aquaculture stocks. The regulations at 50 CFR 21.48 (Public...

  1. Crew Escape Technologies (CREST) Mission Area Requirements Study Current and Future Crew Escape Requirements

    Science.gov (United States)

    1992-02-01

    anthropometry and the type and location of the equipment worn by the test suboect. Based upon the data taken In the early nineteen sixties it was...3.1.1 of the CREST Specification describes the system as having -Flow stagnation fence to reduce windblast Induced loads on the head, torso and upper

  2. CSUB CREST Research on Climate Change and the San Joaquin Valley, CA

    Science.gov (United States)

    Krugh, W. C.; Negrini, R. M.; Baron, D.; Gillespie, J.; Horton, R. A.; Montoya, E.; Cruz-Boone, C.; Andrews, G. D.; Guo, J.

    2015-12-01

    As part of the NSF-supported Centers for Excellence in Science and Technology (CREST), student and faculty researchers at California State University, Bakersfield (CSUB) have been investigating the regional impacts of climate change as well as evaluating the potential of local contributions to its abatement. Highlights of this research include; 1) the development of a high-resolution climate record from Tulare Lake sediments that spans the past 20,000 years, 2) the quantitative analysis and prediction of climate change impacts on Sierra Nevada snowpack, 3) the detailed subsurface characterization of San Joaquin Valley oilfields targeted for CO2 sequestration, and 4) the evaluation of proposed host rock suitability under simulated CO2 injection conditions. To date, CSUB CREST supported research has resulted in 26 contributions to peer-reviewed journals (currently published or in-review). A primary goal of CSUB CREST is to improve the recruitment, retention, and success of students from the local community, the majority of whom are from backgrounds under-represented in STEM disciplines. More than 28 students have been directly involved in the basic and applied research projects supported by this program. The majority of these students have received, or are on track to receive, an M.S. degree and have ultimately gained employment in a STEM field or been accepted into a Ph.D. program. This presentation, and others in this session, will focus on the accomplishments, challenges, and strategies for success gleaned from CSUB CREST Phase 1.

  3. 78 FR 25263 - Eagle Mountain Pumped Storage Hydroelectric Project; Eagle Crest Energy; Notice of Meeting With...

    Science.gov (United States)

    2013-04-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project; Eagle Crest Energy... Power Act), on the Eagle Mountain Pumped Storage Hydroelectric Project. e. All local, state, and...

  4. Overtopping Flow Impact on a Vertical Wall on a Dike Crest

    NARCIS (Netherlands)

    Chen, X.; Hofland, B.; Altomare, C.; Uijttewaal, J.S.W.

    2014-01-01

    In this paper the impact process and mechanism of overtopping flow on a vertical wall on a dike crest are investigated by means of a series of physical model tests. A double-peaked force was recognized in a time series of an overtoping flow. Four stages were summarized for the whole overtopping flow

  5. Decline of traditional rice farming constrains the recovery of the endangered Asian crested ibis (Nipponia nippon).

    Science.gov (United States)

    Sun, Yiwen; Wang, Tiejun; Skidmore, Andrew K; Wang, Qi; Ding, Changqing

    2015-12-01

    Traditional agriculture benefits a rich diversity of plants and animals. The winter-flooded rice fields in the Qinling Mountains, China, are the last refuge for the endangered Asian crested ibis (Nipponia nippon), and intensive efforts have been made to protect this anthropogenic habitat. Analyses of multi-temporal satellite data indicate that winter-flooded rice fields have been continuously reduced across the current range of crested ibis during the past two decades. The rate of loss of these fields in the core-protected areas has unexpectedly increased to a higher level than that in non-protected areas in the past decade. The best fit (R (2) = 0.87) numerical response model of the crested ibis population shows that a reduction of winter-flooded rice fields decreases population growth and predicts that the population growth will be constrained by the decline of traditional winter-flooded rice fields in the coming decades. Our findings suggest that the decline of traditional rice farming is likely to continue to pose a threat to the long-term survival and recovery of the crested ibis population in China.

  6. 77 FR 4274 - Migratory Bird Permits; Double-Crested Cormorant Management in the United States

    Science.gov (United States)

    2012-01-27

    ... Environmental Assessment on the development of revised regulations governing the management of double- crested cormorants. Under current regulations, cormorant damage management activities are conducted annually at the... Management in the United States AGENCY: Fish and Wildlife Service, Interior. ACTION: Request for comments...

  7. 77 FR 43280 - Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy; Notice of Meeting With...

    Science.gov (United States)

    2012-07-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Eagle Mountain Pumped Storage Hydroelectric Project, Eagle Crest Energy... Management Act and the Federal Power Act), on the Eagle Mountain Pumped Storage Hydroelectric Project. e....

  8. Regulators of gene expression in Enteric Neural Crest Cells are putative Hirschsprung disease genes

    NARCIS (Netherlands)

    Schriemer, Duco; Sribudiani, Yunia; IJpma, Arne; Natarajan, Dipa; MacKenzie, Katherine C.; Metzger, Marco; Binder, Ellen; Burns, Alan J.; Thapar, Nikhil; Hofstra, Robert M. W.; Eggen, Bart J. L.

    2016-01-01

    The enteric nervous system (ENS) is required for peristalsis of the gut and is derived from Enteric Neural Crest Cells (ENCCs). During ENS development, the RET receptor tyrosine kinase plays a critical role in the proliferation and survival of ENCCs, their migration along the developing gut, and dif

  9. Regulators of gene expression in Enteric Neural Crest Cells are putative Hirschsprung disease genes

    NARCIS (Netherlands)

    Schriemer, Duco; Sribudiani, Yunia; IJpma, Arne; Natarajan, Dipa; MacKenzie, Katherine C; Metzger, Marco; Binder, Ellen; Burns, Alan J; Thapar, Nikhil; Hofstra, Robert M W; Eggen, Bart J L

    2016-01-01

    The enteric nervous system (ENS) is required for peristalsis of the gut and is derived from enteric neural crest cells (ENCCs). During ENS development, the RET receptor tyrosine kinase plays a critical role in the proliferation and survival of ENCCs, their migration along the developing gut, and dif

  10. Nesting habitat requirements and nestling diet in the Mediterranean populations of Crested Tits Lophophanes cristatus

    NARCIS (Netherlands)

    Atienzar, F.; Barba, E.; Holleman, L.J.M.; Belda, E.J.

    2009-01-01

    Most bird species show specific habitat requirements for breeding and feeding. We studied the pattern of habitat occupation, nestling diet and breeding performance of Crested Tits Lophophanes cristatus in a “typical” (coniferous) and an “atypical” (Holm Oak Quercus ilex) forest in eastern Spain duri

  11. A numerical study of lowest-order short-crested water wave instabilities

    DEFF Research Database (Denmark)

    Fuhrman, David R.; Madsen, Per A.

    2005-01-01

    This work presents the first numerical simulations of the long-term evolution of doubly-periodic short-crested wave instabilities, which are the simplest cases involving the three-dimensional instability of genuinely three-dimensional progressive water waves. The simulated evolutions reveal...

  12. Nest box use and productivity of great crested flycatchers in prescribed-burned longleaf pine forests

    Science.gov (United States)

    White, D.H.; Seginak, J.T.

    2000-01-01

    Managing for the endangered Red-cockaded Woodpecker (Picoides borealis) on federal lands requires burning large tracts of mature pine forests every 3-5 yr. Many cavity trees that serve as potential nest sites for primary and secondary hole-nesting birds are destroyed by fire. We assessed the efficacy of a nest box program for the Great Crested Flycatcher (Myiarchus crinitus) at Carolina Sandhills National Wildlife Refuge, an area intensively managed for Red-cockaded Woodpeckers. During 1996-1998, we installed and monitored 330 (30 in each of 11 sites) nest boxes in mature (>60 yr) longleaf pine (Pinus palustris) tracts that were burned either in April-June (warm season) or December-March (cool season). Prescribed-burned sites were nearly devoid of snags; we estimated only 0.8/ ha in cool-season burns and 1.7/ha in warm-season burns. Great Crested Flycatchers built nests in 20% of the boxes available to them. Clutch sizes were larger in warm-season burns than in cool-season burns, but fledging success (fledglings/nest hatching -1 egg) was lower. Twenty-two of 59 Great Crested Flycatcher nests were depredated and the proportions in each burn class were similar. We recommend the installation of nest boxes for Great Crested Flycatchers in prescribed-burned pine forests, but additional research is needed in these habitats on nest depredation rates and causes.

  13. T-CREST: Time-predictable multi-core architecture for embedded systems

    DEFF Research Database (Denmark)

    Schoeberl, Martin; Abbaspourseyedi, Sahar; Jordan, Alexander

    2015-01-01

    Real-time systems need time-predictable platforms to allow static analysis of the worst-case execution time (WCET). Standard multi-core processors are optimized for the average case and are hardly analyzable. Within the T-CREST project we propose novel solutions for time-predictable multi-core ar...

  14. Evolution of cranial development and the role of neural crest: insights from amphibians.

    Science.gov (United States)

    Hanken, James; Gross, Joshua B

    2005-11-01

    Contemporary studies of vertebrate cranial development document the essential role played by the embryonic neural crest as both a source of adult tissues and a locus of cranial form and patterning. Yet corresponding and basic features of cranial evolution, such as the extent of conservation vs. variation among species in the contribution of the neural crest to specific structures, remain to be adequately resolved. Investigation of these features requires comparable data from species that are both phylogenetically appropriate and taxonomically diverse. One key group are amphibians, which are uniquely able to inform our understanding of the ancestral patterns of ontogeny in fishes and tetrapods as well as the evolution of presumably derived patterns reported for amniotes. Recent data support the hypothesis that a prominent contribution of the neural crest to cranial skeletal and muscular connective tissues is a fundamental property that evolved early in vertebrate history and is retained in living forms. The contribution of the neural crest to skull bones appears to be more evolutionarily labile than that of cartilages, although significance of the limited comparative data is difficult to establish at present. Results underline the importance of accurate and reliable homology assessments for evaluating the contrasting patterns of derivation reported for the three principal tetrapod models: mouse, chicken and frog.

  15. 77 FR 5505 - Eagle Crest Energy Company; Notice of Availability of the Final Environmental Impact Statement...

    Science.gov (United States)

    2012-02-03

    ... Energy Regulatory Commission Eagle Crest Energy Company; Notice of Availability of the Final Environmental Impact Statement for the Eagle Mountain Pumped Storage Hydroelectric Project In accordance with... of Energy Projects has reviewed the application for license for the Eagle Mountain Pumped...

  16. 76 FR 1149 - Eagle Crest Energy Company; Notice of Availability of the Draft Environmental Impact Statement...

    Science.gov (United States)

    2011-01-07

    ... Federal Energy Regulatory Commission Eagle Crest Energy Company; Notice of Availability of the Draft Environmental Impact Statement for the Eagle Mountain Pumped Storage Hydroelectric Project and Notice of Public... for the Eagle Mountain Pumped Storage Hydroelectric Project (FERC No. 13123), located on the site...

  17. Pelvic instability after bone graft harvesting from posterior iliac crest: report of nine patients

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.; Pathria, M.; Jacobson, J. [Dept. of Radiology, Univ. of California, San Diego, CA (United States); Resnick, D. [Dept. of Radiology, Veterans Affairs Medical Center, San Diego, CA (United States)

    2001-05-01

    Objective. To report the imaging findings in nine patients who developed pelvic instability after bone graft harvest from the posterior aspect of the iliac crest.Design and patients. A retrospective study was performed of the imaging studies of nine patients who developed pelvic pain after autologous bone graft was harvested from the posterior aspect of the ilium for spinal arthrodesis. Plain films, bone scans, and CT and MR examinations of the pelvis were reviewed. Pertinent aspects of the clinical history of these patients were noted, including age, gender and clinical symptoms.Results. The age of the patients ranged from 52 to 77 years (average 69 years) and all were women. The bone graft had been derived from the posterior aspect of the iliac crest about the sacroiliac joint. All patients subsequently developed subluxation of the pubic symphysis. Eight patients had additional insufficiency fractures of the iliac crest adjacent to the bone graft donor site, and five patients also revealed subluxation of the sacroiliac joint. Two had insufficiency fractures of the sacrum and one had an additional fracture of the pubic ramus.Conclusions. Pelvic instability is a potential complication of bone graft harvesting from the posterior aspect of the iliac crest. The pelvic instability is manifested by insufficiency fractures of the ilium and subluxation of the sacroiliac joints and pubic symphysis. (orig.)

  18. Computerized determination of 3-D connectivity density in human iliac crest bone biopsies

    DEFF Research Database (Denmark)

    Thomsen, J.S.; Mosekilde, Li.; Barlach, J.;

    1996-01-01

    Combining the physical disector principle with an algorithm for automatic non-linear alignment of disector pairs we have developed a software system for direct measurement of 3D connectivity densities in iliac crest bone biopsies. The method was applied to biopsies from 14 non-selected autopsy...

  19. Ontogeny in the tube-crested dinosaur Parasaurolophus (Hadrosauridae and heterochrony in hadrosaurids

    Directory of Open Access Journals (Sweden)

    Andrew A. Farke

    2013-10-01

    Full Text Available The tube-crested hadrosaurid dinosaur Parasaurolophus is remarkable for its unusual cranial ornamentation, but little is known about its growth and development, particularly relative to well-documented ontogenetic series for lambeosaurin hadrosaurids (such as Corythosaurus, Lambeosaurus, and Hypacrosaurus. The skull and skeleton of a juvenile Parasaurolophus from the late Campanian-aged (∼75.5 Ma Kaiparowits Formation of southern Utah, USA, represents the smallest and most complete specimen yet described for this taxon. The individual was approximately 2.5 m in body length (∼25% maximum adult body length at death, with a skull measuring 246 mm long and a femur 329 mm long. A histological section of the tibia shows well-vascularized, woven and parallel-fibered primary cortical bone typical of juvenile ornithopods. The histological section revealed no lines of arrested growth or annuli, suggesting the animal may have still been in its first year at the time of death. Impressions of the upper rhamphotheca are preserved in association with the skull, showing that the soft tissue component for the beak extended for some distance beyond the limits of the oral margin of the premaxilla. In marked contrast with the lengthy tube-like crest in adult Parasaurolophus, the crest of the juvenile specimen is low and hemicircular in profile, with an open premaxilla-nasal fontanelle. Unlike juvenile lambeosaurins, the nasal passages occupy nearly the entirety of the crest in juvenile Parasaurolophus. Furthermore, Parasaurolophus initiated development of the crest at less than 25% maximum skull size, contrasting with 50% of maximum skull size in hadrosaurs such as Corythosaurus. This early development may correspond with the larger and more derived form of the crest in Parasaurolophus, as well as the close relationship between the crest and the respiratory system. In general, ornithischian dinosaurs formed bony cranial ornamentation at a relatively younger age

  20. Static histomorphometry of human iliac crest and vertebral trabecular bone: a comparative study.

    Science.gov (United States)

    Thomsen, J S; Ebbesen, E N; Mosekilde, Li

    2002-01-01

    We recently developed a new, rapid method for conducting static histomorphometry on large histologic sections. This method has now been applied on both iliac crest and lumbar vertebral bone to compare the age-related changes at these two skeletal sites and to investigate the correlation between the histomorphometric measures at the iliac crest and the vertebral body. The material comprised matched sets of unilateral transiliac crest bone biopsies and lumbar vertebral bodies (L-2) from 24 women (19-96 years) and 24 men (23-95 years) selected from a larger autopsy material. Three female subjects (80, 88, and 90 years) had a known vertebral fracture of L-2. The iliac crest biopsies and 9-mm-thick mediolateral slices of half the entire vertebral bodies were embedded in methylmetacrylate, stained with aniline blue, and scanned into a computer with a flatbed image scanner at a high resolution. With a custom-made computer program the following static histomorphometric measures were determined: trabecular bone volume; marrow and bone space star volume; node-strut analysis; trabecular bone pattern factor; trabecular thickness; trabecular number; trabecular separation; and anisotropy of bone and marrow phase. In addition, connectivity density was measured (ConnEulor method). The results showed that the age-related changes in the static histomorphometric measures are generally similar in the iliac crest and the vertebral body, and that these age-related changes are independent of gender. An exception, however, is connectivity density, where the age-related changes are similar for women and men in the vertebral body but significantly different in the iliac crest. Furthermore, the results showed that the histomorphometric measures were weakly intercorrelated between the iliac crest and the vertebral body, despite the generally similar pattern in age-related changes at these two skeletal sites. The highest correlation coefficient was found for trabecular separation (Tb.Sp; r = 0

  1. Integration of signals along orthogonal axes of the vertebrate neural tube controls progenitor competence and increases cell diversity.

    Directory of Open Access Journals (Sweden)

    Noriaki Sasai

    2014-07-01

    Full Text Available A relatively small number of signals are responsible for the variety and pattern of cell types generated in developing embryos. In part this is achieved by exploiting differences in the concentration or duration of signaling to increase cellular diversity. In addition, however, changes in cellular competence-temporal shifts in the response of cells to a signal-contribute to the array of cell types generated. Here we investigate how these two mechanisms are combined in the vertebrate neural tube to increase the range of cell types and deliver spatial control over their location. We provide evidence that FGF signaling emanating from the posterior of the embryo controls a change in competence of neural progenitors to Shh and BMP, the two morphogens that are responsible for patterning the ventral and dorsal regions of the neural tube, respectively. Newly generated neural progenitors are exposed to FGF signaling, and this maintains the expression of the Nk1-class transcription factor Nkx1.2. Ventrally, this acts in combination with the Shh-induced transcription factor FoxA2 to specify floor plate cells and dorsally in combination with BMP signaling to induce neural crest cells. As development progresses, the intersection of FGF with BMP and Shh signals is interrupted by axis elongation, resulting in the loss of Nkx1.2 expression and allowing the induction of ventral and dorsal interneuron progenitors by Shh and BMP signaling to supervene. Hence a similar mechanism increases cell type diversity at both dorsal and ventral poles of the neural tube. Together these data reveal that tissue morphogenesis produces changes in the coincidence of signals acting along orthogonal axes of the neural tube and this is used to define spatial and temporal transitions in the competence of cells to interpret morphogen signaling.

  2. Integration of signals along orthogonal axes of the vertebrate neural tube controls progenitor competence and increases cell diversity.

    Science.gov (United States)

    Sasai, Noriaki; Kutejova, Eva; Briscoe, James

    2014-07-01

    A relatively small number of signals are responsible for the variety and pattern of cell types generated in developing embryos. In part this is achieved by exploiting differences in the concentration or duration of signaling to increase cellular diversity. In addition, however, changes in cellular competence-temporal shifts in the response of cells to a signal-contribute to the array of cell types generated. Here we investigate how these two mechanisms are combined in the vertebrate neural tube to increase the range of cell types and deliver spatial control over their location. We provide evidence that FGF signaling emanating from the posterior of the embryo controls a change in competence of neural progenitors to Shh and BMP, the two morphogens that are responsible for patterning the ventral and dorsal regions of the neural tube, respectively. Newly generated neural progenitors are exposed to FGF signaling, and this maintains the expression of the Nk1-class transcription factor Nkx1.2. Ventrally, this acts in combination with the Shh-induced transcription factor FoxA2 to specify floor plate cells and dorsally in combination with BMP signaling to induce neural crest cells. As development progresses, the intersection of FGF with BMP and Shh signals is interrupted by axis elongation, resulting in the loss of Nkx1.2 expression and allowing the induction of ventral and dorsal interneuron progenitors by Shh and BMP signaling to supervene. Hence a similar mechanism increases cell type diversity at both dorsal and ventral poles of the neural tube. Together these data reveal that tissue morphogenesis produces changes in the coincidence of signals acting along orthogonal axes of the neural tube and this is used to define spatial and temporal transitions in the competence of cells to interpret morphogen signaling.

  3. 26 CFR 301.6332-2 - Surrender of property subject to levy in the case of life insurance and endowment contracts.

    Science.gov (United States)

    2010-04-01

    ... policy by the taxpayer or by the death of the insured on a date before the 90th day after service of the... case of life insurance and endowment contracts. 301.6332-2 Section 301.6332-2 Internal Revenue INTERNAL... the case of life insurance and endowment contracts. (a) In general. This section provides...

  4. 45 CFR 1159.16 - Will the Endowment take steps to ensure that its employees involved with its systems of records...

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Will the Endowment take steps to ensure that its employees involved with its systems of records are familiar with the requirements and implications of the... PRIVACY ACT OF 1974 § 1159.16 Will the Endowment take steps to ensure that its employees involved with...

  5. A pilot study investigating the utilization of crest pads for treatment of toe callus and ulceration.

    Science.gov (United States)

    Melo, Monica; Bernecker, Tricia; McCullough, James; Hong, John; Trumbauer, Jane Scott; Miller, Mary Ellen

    2015-12-01

    Patients with lesser-toe deformities are at increased risk of developing calluses and ulcers on the distal ends of the affected digits because of the increased pressures applied to these areas. The number of diabetic patients in the United States continues to increase, along with associated comorbidities such as peripheral vascular disease and peripheral neuropathy. These conditions predispose patients to developing foot ulcerations, especially if foot deformities are present. Crest pads are a simple-to-make, inexpensive option to treat calluses and ulcerations on the distal ends of digits; however, there is no research available that support their use. Crest pads consist of rolled gauze covered in moleskin, with a large opening that fits over several toes and lies on the dorsal aspect of the foot, with the padded portion resting under the toes. Over several days of use, the pad molds to the plantar aspect of the toes, offloading pressure from the distal end of the affected digit(s). The sample was obtained through a retrospective chart review of patients identified as having had at least one nail care visit and at least one follow-up visit at a vascular surgery practice between August 2011 and December 2014. Potential subjects with toe deformities who presented with callus or ulcer on the distal end of a digit were considered for inclusion, if they received a crest pad as part of their treatment plan. The scholarly project was a preintervention or postintervention design with subjects acting as their own controls. McNemar's test was used to analyze the results which were statistically significant (P ulcer improvement following the crest pad intervention. The results of this scholarly project support the use of crest pads in patients with lesser-toe deformities to treat distal toe calluses and/or ulcerations.

  6. Novel structural components of the ventral disc and lateral crest in Giardia intestinalis.

    Directory of Open Access Journals (Sweden)

    Kari D Hagen

    2011-12-01

    Full Text Available Giardia intestinalis is a ubiquitous parasitic protist that is the causative agent of giardiasis, one of the most common protozoan diarrheal diseases in the world. Giardia trophozoites attach to the intestinal epithelium using a specialized and elaborate microtubule structure, the ventral disc. Surrounding the ventral disc is a less characterized putatively contractile structure, the lateral crest, which forms a continuous perimeter seal with the substrate. A better understanding of ventral disc and lateral crest structure, conformational dynamics, and biogenesis is critical for understanding the mechanism of giardial attachment to the host. To determine the components comprising the ventral disc and lateral crest, we used shotgun proteomics to identify proteins in a preparation of isolated ventral discs. Candidate disc-associated proteins, or DAPs, were GFP-tagged using a ligation-independent high-throughput cloning method. Based on disc localization, we identified eighteen novel DAPs, which more than doubles the number of known disc-associated proteins. Ten of the novel DAPs are associated with the lateral crest or outer edge of the disc, and are the first confirmed components of this structure. Using Fluorescence Recovery After Photobleaching (FRAP with representative novel DAP::GFP strains we found that the newly identified DAPs tested did not recover after photobleaching and are therefore structural components of the ventral disc or lateral crest. Functional analyses of the novel DAPs will be central toward understanding the mechanism of ventral disc-mediated attachment and the mechanism of disc biogenesis during cell division. Since attachment of Giardia to the intestine via the ventral disc is essential for pathogenesis, it is possible that some proteins comprising the disc could be potential drug targets if their loss or disruption interfered with disc biogenesis or function, preventing attachment.

  7. Oral Crest Lengthening for Increasing Removable Denture Retention by Means of CO2 Laser

    Directory of Open Access Journals (Sweden)

    Samir Nammour

    2014-01-01

    Full Text Available The loss of teeth and their replacement by artificial denture is associated with many problems. The denture needs a certain amount of ridge height to give it retention and a long-term function. Crest lengthening procedures are performed to provide a better anatomic environment and to create proper supporting structures for more stability and retention of the denture. The purpose of our study is to describe and evaluate the effectiveness of CO2 laser-assisted surgery in patients treated for crest lengthening (vestibular deepening. There have been various surgical techniques described in order to restore alveolar ridge height by pushing muscles attaching of the jaws. Most of these techniques cause postoperative complications such as edemas, hemorrhage, pain, infection, slow healing, and rebound to initial position. Our clinical study describes the treatment planning and clinical steps for the crest lengthening with the use of CO2 laser beam (6–15 Watts in noncontact, energy density range: 84.92–212.31 J/cm2, focus, and continuous mode with a focal point diameter of 0.3 mm. At the end of each surgery, dentures were temporarily relined with a soft material. Patients were asked to mandatorily wear their relined denture for a minimum of 4–6 weeks and to remove it for hygienic purposes. At the end of each surgery, the deepest length of the vestibule was measured by the operator. No sutures were made and bloodless wounds healed in second intention without grafts. Results pointed out the efficiency of the procedure using CO2 laser. At 8 weeks of post-op, the mean of crest lengthening was stable without rebound. Only a loss of 15% was noticed. To conclude, the use of CO2 laser is an effective option for crest lengthening.

  8. Regulation of the nascent brain vascular network by neural progenitors.

    Science.gov (United States)

    Santhosh, Devi; Huang, Zhen

    2015-11-01

    Neural progenitors are central players in the development of the brain neural circuitry. They not only produce the diverse neuronal and glial cell types in the brain, but also guide their migration in this process. Recent evidence indicates that neural progenitors also play a critical role in the development of the brain vascular network. At an early stage, neural progenitors have been found to facilitate the ingression of blood vessels from outside the neural tube, through VEGF and canonical Wnt signaling. Subsequently, neural progenitors directly communicate with endothelial cells to stabilize nascent brain vessels, in part through down-regulating Wnt pathway activity. Furthermore, neural progenitors promote nascent brain vessel integrity, through integrin αvβ8-dependent TGFβ signaling. In this review, we will discuss the evidence for, as well as questions that remain, regarding these novel roles of neural progenitors and the underlying mechanisms in their regulation of the nascent brain vascular network.

  9. Natural Resources Endowment, Economic Rights Endowment and Regional Economic Growth%自然资源禀赋、经济权利禀赋与区域经济增长

    Institute of Scientific and Technical Information of China (English)

    林勇; 朱忠杰; 张瑞

    2014-01-01

    This paper takes the panel data from 2000 to 2011 in 31 provinces of China to build spatial econometric model , and incorporates the economic rights endowment into the analytical framework of natural resources endowment and regional economic growth by spatial panel method , to analyze the effects of natural resources endowment and economic rights endow -ment on regional economic growth .The research results show that natural resources endowment is positive correlations with regional economic growth , and the abundance of natural resources can promote regional economic growth to a certain , but has little effect; besides, in the economic rights endowment , both of physical capital rights and the right to use the labor are positive correlations with the economic growth , and has more effect; human capital rights is negative correlations with regional economic growth , but is not significant; the institutional change rights is positive correlation with regional econom-ic growth, the system supply rights is positive correlations with regional economic growth , but is not significant .%本文选取2000-2011年中国31个省级单元的面板数据构建空间计量模型,采用空间面板方法将经济权利禀赋纳入自然资源禀赋与区域经济增长的分析框架,探讨自然资源禀赋、经济权利禀赋对区域经济增长的影响。研究发现自然资源禀赋与区域经济增长显著正相关,自然资源丰裕在一定程度上能促进地区经济增长,但作用力较小;在经济权利禀赋中,物质资本权利、劳动力使用权利与区域经济增长显著正相关,且作用力度较大;人力资本权利与区域经济增长负相关,但不显著;制度变迁权利与区域经济增长显著正相关,而制度供给权利与区域经济增长虽正相关,但不显著。

  10. Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae).

    Science.gov (United States)

    Reyes, Michelle; Zandberg, Katrina; Desmawati, Iska; de Bellard, Maria E

    2010-05-18

    The neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their development in non-avian reptiles like snakes and lizards. In this study, we show for the first time ever trunk neural crest migration in a snake by labeling it with DiI and immunofluorescence. As in birds and mammals, we find that early migrating trunk neural crest cells use both a ventromedial pathway and an inter-somitic pathway in the snake. However, unlike birds and mammals, we also observed large numbers of late migrating neural crest cells utilizing the inter-somitic pathway in snake. We found that while trunk neural crest migration in snakes is very similar to that of other amniotes, the inter-somitic pathway is used more extensively by late-migrating trunk neural crest cells in snake.

  11. Identification and dissection of a key enhancer mediating cranial neural crest specific expression of transcription factor, Ets-1.

    Science.gov (United States)

    Barembaum, Meyer; Bronner, Marianne E

    2013-10-15

    Neural crest cells form diverse derivatives that vary according to their level of origin along the body axis, with only cranial neural crest cells contributing to facial skeleton. Interestingly, the transcription factor Ets-1 is uniquely expressed in cranial but not trunk neural crest, where it functions as a direct input into neural crest specifier genes, Sox10 and FoxD3. We have isolated and interrogated a cis-regulatory element, conserved between birds and mammals, that drives reporter expression in a manner that recapitulates that of endogenous Ets-1 expression in the neural crest. Within a minimal Ets-1 enhancer region, mutation of putative binding sites for SoxE, homeobox, Ets, TFAP2 or Fox proteins results in loss or reduction of neural crest enhancer activity. Morpholino-mediated loss-of-function experiments show that Sox9, Pax7, Msx1/2, Ets-1, TFAP2A and FoxD3, all are required for enhancer activity. In contrast, mutation of a putative cMyc/E-box sequence augments reporter expression, consistent with this being a repressor binding site. Taken together, these results uncover new inputs into Ets-1, revealing critical links in the cranial neural crest gene regulatory network. © 2013 Elsevier Inc. All rights reserved.

  12. miR-21 promotes the differentiation of hair follicle-derived neural crest stem cells into Schwann cells

    Institute of Scientific and Technical Information of China (English)

    Yuxin Ni; Kaizhi Zhang; Xuejuan Liu; Tingting Yang; Baixiang Wang; Li Fu; Lan A; Yanmin Zhou

    2014-01-01

    Hair follicle-derived neural crest stem cells can be induced to differentiate into Schwann cells in vivo and in vitro. However, the underlying regulatory mechanism during cell differentiation remains poorly understood. This study isolated neural crest stem cells from human hair folli-cles and induced them to differentiate into Schwann cells. Quantitative RT-PCR showed that microRNA (miR)-21 expression was gradually increased during the differentiation of neural crest stem cells into Schwann cells. After transfection with the miR-21 agonist (agomir-21), the differentiation capacity of neural crest stem cells was enhanced. By contrast, after transfection with the miR-21 antagonist (antagomir-21), the differentiation capacity was attenuated. Further study results showed that SOX-2 was an effective target of miR-21. Without compromising SOX2 mRNA expression, miR-21 can down-regulate SOX protein expression by binding to the 3′-UTR of miR-21 mRNA. Knocking out the SOX2 gene from the neural crest stem cells significantly reversed the antagomir-21 inhibition of neural crest stem cells differentiating into Schwann cells. The results suggest that miR-21 expression was increased during the differentiation of neural crest stem cells into Schwann cells and miR-21 promoted the differentiation through down-regu-lating SOX protein expression by binding to the 3′-UTR of SOX2 mRNA.

  13. A statistical study of single crest phenomenon in the equatorial ionospheric anomaly region using Swarm A satellite

    Science.gov (United States)

    Fathy, Adel; Ghamry, Essam

    2017-03-01

    Though the Equatorial Ionospheric Anomaly (EIA) is represented by two crests within ±15° latitude, a single crest is also observed in the entire ionosphere. Few studies have addressed single crest phenomena. A statistical study of 2237 single crest phenomenon from the in situ electron density measurements of Swarm A satellite was investigated during December 2013-December 2015. Our analysis focused on local time, seasonal, and both geographic and geomagnetic latitudinal variations. Our results show the following observations: 1 - The maximum number of events peaks mainly in the dayside region around 0800-1200 LT and these occur mainly within the magnetic equator. 2 - The maximum amplitude of the single crests take place most prominently during equinoxes. 3 - The majority of single crests occur in the northern hemisphere. 4 - The seasonal distribution of the events shows that the summer events are located further from the magnetic equator in the northern hemisphere and shift their locations into the southern hemisphere in winter, while spring events are centered along the magnetic equator. 5 - Dayside single crest events appear close to the magnetic equator and more centered on the equator in winter season. 6 - Dawn, night and dusk side events reverse their location from northern hemisphere in summer to southern hemisphere in winter.

  14. Neural crest-derived mesenchymal cells require Wnt signaling for their development and drive invagination of the telencephalic midline.

    Directory of Open Access Journals (Sweden)

    Youngshik Choe

    Full Text Available Embryonic neural crest cells contribute to the development of the craniofacial mesenchyme, forebrain meninges and perivascular cells. In this study, we investigated the function of ß-catenin signaling in neural crest cells abutting the dorsal forebrain during development. In the absence of ß-catenin signaling, neural crest cells failed to expand in the interhemispheric region and produced ectopic smooth muscle cells instead of generating dermal and calvarial mesenchyme. In contrast, constitutive expression of stabilized ß-catenin in neural crest cells increased the number of mesenchymal lineage precursors suggesting that ß-catenin signaling is necessary for the expansion of neural crest-derived mesenchymal cells. Interestingly, the loss of neural crest-derived mesenchymal stem cells (MSCs leads to failure of telencephalic midline invagination and causes ventricular system defects. This study shows that ß-catenin signaling is required for the switch of neural crest cells to MSCs and mediates the expansion of MSCs to drive the formation of mesenchymal structures of the head. Furthermore, loss of these structures causes striking defects in forebrain morphogenesis.

  15. Mobilization of hematopoietic progenitor cells in patients with liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Ursula; M; Gehling; Marc; Willems; Kathleen; Schlagner; Ralf; A; Benndorf; Maura; Dandri; Jrg; Petersen; Martina; Sterneck; Joerg-Matthias; Pollok; Dieter; K; Hossfeld; Xavier; Rogiers

    2010-01-01

    AIM:To test the hypothesis that liver cirrhosis is associated with mobilization of hematopoietic progenitor cells. METHODS:Peripheral blood samples from 72 patients with liver cirrhosis of varying etiology were analyzed by flow cytometry.Identified progenitor cell subsets were immunoselected and used for functional assays in vitro. Plasma levels of stromal cell-derived factor-1(SDF-1) were measured using an enzyme linked immunosorbent assay.RESULTS:Progenitor cells with a CD133 + /CD45 + CD14 + phenotype we...

  16. Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells

    Science.gov (United States)

    2015-09-01

    AWARD NUMBER: W81XWH-13-1-0244 TITLE: Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells PRINCIPAL...2014 - 31 Aug 2015 4. TITLE AND SUBTITLE Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells 5a. CONTRACT NUMBER 5b...the development of knee osteoarthritis (OA). New treatments centered on the stem/ progenitor cell population resident within the adult meniscus will be

  17. No fitness cost of glyphosate resistance endowed by massive EPSPS gene amplification in Amaranthus palmeri.

    Science.gov (United States)

    Vila-Aiub, Martin M; Goh, Sou S; Gaines, Todd A; Han, Heping; Busi, Roberto; Yu, Qin; Powles, Stephen B

    2014-04-01

    Amplification of the EPSPS gene has been previously identified as the glyphosate resistance mechanism in many populations of Amaranthus palmeri, a major weed pest in US agriculture. Here, we evaluate the effects of EPSPS gene amplification on both the level of glyphosate resistance and fitness cost of resistance. A. palmeri individuals resistant to glyphosate by expressing a wide range of EPSPS gene copy numbers were evaluated under competitive conditions in the presence or absence of glyphosate. Survival rates to glyphosate and fitness traits of plants under intra-specific competition were assessed. Plants with higher amplification of the EPSPS gene (53-fold) showed high levels of glyphosate resistance, whereas less amplification of the EPSPS gene (21-fold) endowed a lower level of glyphosate resistance. Without glyphosate but under competitive conditions, plants exhibiting up to 76-fold EPSPS gene amplification exhibited similar height, and biomass allocation to vegetative and reproductive organs, compared to glyphosate susceptible A. palmeri plants with no amplification of the EPSPS gene. Both the additive effects of EPSPS gene amplification on the level of glyphosate resistance and the lack of associated fitness costs are key factors contributing to EPSPS gene amplification as a widespread and important glyphosate resistance mechanism likely to become much more evident in weed plant species.

  18. In Situ and Ex Situ Low-Field NMR Spectroscopy and MRI Endowed by SABRE Hyperpolarization**

    Science.gov (United States)

    Barskiy, Danila A.; Kovtunov, Kirill V.; Koptyug, Igor V.; He, Ping; Groome, Kirsten A.; Best, Quinn A.; Shi, Fan; Goodson, Boyd M.; Shchepin, Roman V.; Truong, Milton L.; Coffey, Aaron M.; Waddell, Kevin W.; Chekmenev, Eduard Y.

    2015-01-01

    By using 5.75 and 47.5 mT nuclear magnetic resonance (NMR) spectroscopy, up to 105-fold sensitivity enhancement through signal amplification by reversible exchange (SABRE) was enabled, and subsecond temporal resolution was used to monitor an exchange reaction that resulted in the buildup and decay of hyperpolarized species after parahydrogen bubbling. We demonstrated the high-resolution low-field proton magnetic resonance imaging (MRI) of pyridine in a 47.5 mT magnetic field endowed by SABRE. Molecular imaging (i.e. imaging of dilute hyperpolarized substances rather than the bulk medium) was conducted in two regimes: in situ real-time MRI of the reaction mixture (in which pyridine was hyperpolarized), and ex situ MRI (in which hyperpolarization decays) of the liquid hyperpolarized product. Low-field (milli-Tesla range, e.g. 5.75 and 47.5 mT used in this study) parahydrogen-enhanced NMR and MRI, which are free from the limitations of high-field magnetic resonance (including susceptibility-induced gradients of the static magnetic field at phase interfaces), potentially enables new imaging applications as well as differentiation of hyperpolarized chemical species on demand by exploiting spin manipulations with static and alternating magnetic fields. PMID:25367202

  19. Poverty Dynamics, Ecological Endowments, and Land Use among Smallholders in the Brazilian Amazon

    Science.gov (United States)

    Guedes, Gilvan R.; VanWey, Leah K.; Hull, James R.; Antigo, Mariangela; Barbieri, Alisson F.

    2013-01-01

    Rural settlement in previously sparsely occupied areas of the Brazilian Amazon has been associated with high levels of forest loss and unclear long-term social outcomes. We focus here on the micro-level processes in one settlement area to answer the question of how settler and farm endowments affect household poverty. We analyze the extent to which poverty is sensitive to changes in natural capital, land use strategies, and biophysical characteristics of properties (particularly soil quality). Cumulative time spent in poverty is simulated using Markovian processes, which show that accessibility to markets and land use system are especially important for decreasing poverty among households in our sample. Wealthier households are selected into commercial production of perennials before our initial observation, and are therefore in poverty a lower proportion of the time. Land in pasture, in contrast, has an independent effect on reducing the proportion of time spent in poverty. Taken together, these results show that investments in roads and the institutional structures needed to make commercial agriculture or ranching viable in existing and new settlement areas can improve human well-being in frontiers. PMID:24267754

  20. Poverty dynamics, ecological endowments, and land use among smallholders in the Brazilian Amazon.

    Science.gov (United States)

    Guedes, Gilvan R; VanWey, Leah K; Hull, James R; Antigo, Mariangela; Barbieri, Alisson F

    2014-01-01

    Rural settlement in previously sparsely occupied areas of the Brazilian Amazon has been associated with high levels of forest loss and unclear long-term social outcomes. We focus here on the micro-level processes in one settlement area to answer the question of how settler and farm endowments affect household poverty. We analyze the extent to which poverty is sensitive to changes in natural capital, land use strategies, and biophysical characteristics of properties (particularly soil quality). Cumulative time spent in poverty is simulated using Markovian processes, which show that accessibility to markets and land use system are especially important for decreasing poverty among households in our sample. Wealtheir households are selected into commercial production of perennials before our initial observation, and are therefore in poverty a lower proportion of the time. Land in pasture, in contrast, has an independent effect on reducing the proportion of time spent in poverty. Taken together, these results show that investments in roads and the institutional structures needed to make commercial agriculture or ranching viable in existing and new settlement areas can improve human well-being in frontiers.

  1. Endowing non-cellulolytic microorganisms with cellulolytic activity aiming for consolidated bioprocessing.

    Science.gov (United States)

    Yamada, Ryosuke; Hasunuma, Tomohisa; Kondo, Akihiko

    2013-11-01

    With the exhaustion of fossil fuels and with the environmental issues they pose, utilization of abundant lignocellulosic biomass as a feedstock for biofuels and bio-based chemicals has recently become an attractive option. Lignocellulosic biomass is primarily composed of cellulose, hemicellulose, and lignin and has a very rigid and complex structure. It is accordingly much more expensive to process than starchy grains because of the need for extensive pretreatment and relatively large amounts of cellulases for efficient hydrolysis. Efficient and cost-effective methods for the production of biofuels and chemicals from lignocellulose are required. A consolidated bioprocess (CBP), which integrates all biological steps consisting of enzyme production, saccharification, and fermentation, is considered a promising strategy for reducing production costs. Establishing an efficient CBP using lignocellulosic biomass requires both lignocellulose degradation into glucose and efficient production of biofuels or chemicals from glucose. With this aim, many researchers are attempting to endow selected microorganisms with lignocellulose-assimilating ability. In this review, we focus on studies aimed at conferring lignocellulose-assimilating ability not only to yeast strains but also to bacterial strains by recombinant technology. Recent developments in improvement of enzyme productivity by microorganisms and in improvement of the specific activity of cellulase are emphasized.

  2. PH motifs in PAR1&2 endow breast cancer growth

    Science.gov (United States)

    Kancharla, A.; Maoz, M.; Jaber, M.; Agranovich, D.; Peretz, T.; Grisaru-Granovsky, S.; Uziely, B.; Bar-Shavit, R.

    2015-01-01

    Although emerging roles of protease-activated receptor1&2 (PAR1&2) in cancer are recognized, their underlying signalling events are poorly understood. Here we show signal-binding motifs in PAR1&2 that are critical for breast cancer growth. This occurs via the association of the pleckstrin homology (PH) domain with Akt/PKB as a key signalling event of PARs. Other PH-domain signal-proteins such as Etk/Bmx and Vav3 also associate with PAR1 and PAR2 through their PH domains. PAR1 and PAR2 bind with priority to Etk/Bmx. A point mutation in PAR2, H349A, but not in R352A, abrogates PH-protein association and is sufficient to markedly reduce PAR2-instigated breast tumour growth in vivo and placental extravillous trophoblast (EVT) invasion in vitro. Similarly, the PAR1 mutant hPar1-7A, which is unable to bind the PH domain, reduces mammary tumours and EVT invasion, endowing these motifs with physiological significance and underscoring the importance of these previously unknown PAR1 and PAR2 PH-domain-binding motifs in both pathological and physiological invasion processes. PMID:26600192

  3. Role of cranial neural crest cells in visceral arch muscle positioning and morphogenesis in the Mexican axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Ericsson, Rolf; Cerny, Robert; Falck, Pierre; Olsson, Lennart

    2004-10-01

    The role of cranial neural crest cells in the formation of visceral arch musculature was investigated in the Mexican axolotl, Ambystoma mexicanum. DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine, perchlorate) labeling and green fluorescent protein (GFP) mRNA injections combined with unilateral transplantations of neural folds showed that neural crest cells contribute to the connective tissues but not the myofibers of developing visceral arch muscles in the mandibular, hyoid, and branchial arches. Extirpations of individual cranial neural crest streams demonstrated that neural crest cells are necessary for correct morphogenesis of visceral arch muscles. These do, however, initially develop in their proper positions also in the absence of cranial neural crest. Visceral arch muscles forming in the absence of neural crest cells start to differentiate at their origins but fail to extend toward their insertions and may have a frayed appearance. Our data indicate that visceral arch muscle positioning is controlled by factors that do not have a neural crest origin. We suggest that the cranial neural crest-derived connective tissues provide directional guidance important for the proper extension of the cranial muscles and the subsequent attachment to the insertion on the correct cartilage. In a comparative context, our data from the Mexican axolotl support the view that the cranial neural crest plays a fundamental role in the development of not only the skeleton of the vertebrate head but also in the morphogenesis of the cranial muscles and that this might be a primitive feature of cranial development in vertebrates.

  4. A New Brachylophosaurin Hadrosaur (Dinosauria: Ornithischia with an Intermediate Nasal Crest from the Campanian Judith River Formation of Northcentral Montana.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Freedman Fowler

    Full Text Available Brachylophosaurini is a clade of hadrosaurine dinosaurs currently known from the Campanian (Late Cretaceous of North America. Its members include: Acristavus gagslarsoni, which lacks a nasal crest; Brachylophosaurus canadensis, which possesses a flat paddle-shaped nasal crest projecting posteriorly over the dorsal skull roof; and Maiasaura peeblesorum, which possesses a dorsally-projecting nasofrontal crest. Acristavus, from the lower Two Medicine Formation of Montana (~81-80 Ma, is hypothesized to be the ancestral member of the clade. Brachylophosaurus specimens are from the middle Oldman Formation of Alberta and equivalent beds in the Judith River Formation of Montana; the upper Oldman Formation is dated 77.8 Ma.A new brachylophosaurin hadrosaur, Probrachylophosaurus bergei (gen. et sp. nov. is described and phylogenetically analyzed based on the skull and postcranium of a large individual from the Judith River Formation of northcentral Montana (79.8-79.5 Ma; the horizon is equivalent to the lower Oldman Formation of Alberta. Cranial morphology of Probrachylophosaurus, most notably the nasal crest, is intermediate between Acristavus and Brachylophosaurus. In Brachylophosaurus, the nasal crest lengthens and flattens ontogenetically, covering the supratemporal fenestrae in large adults. The smaller nasal crest of Probrachylophosaurus is strongly triangular in cross section and only minimally overhangs the supratemporal fenestrae, similar to an ontogenetically earlier stage of Brachylophosaurus. Sutural fusion and tibial osteohistology reveal that the holotype of Probrachylophosaurus was relatively more mature than a similarly large Brachylophosaurus specimen; thus, Probrachylophosaurus is not simply an immature Brachylophosaurus.The small triangular posteriorly oriented nasal crest of Probrachylophosaurus is proposed to represent a transitional nasal morphology between that of a non-crested ancestor such as Acristavus and the large flat

  5. Lin28 sustains early renal progenitors and induces Wilms tumor

    National Research Council Canada - National Science Library

    Urbach, Achia; Yermalovich, Alena; Zhang, Jin; Spina, Catherine S; Zhu, Hao; Perez-Atayde, Antonio R; Shukrun, Rachel; Charlton, Jocelyn; Sebire, Neil; Mifsud, William; Dekel, Benjamin; Pritchard-Jones, Kathy; Daley, George Q

    2014-01-01

    .... Here we show that overexpression of the heterochronic regulator Lin28 during kidney development in mice markedly expands nephrogenic progenitors by blocking their final wave of differentiation...

  6. Lack of beta1 integrins in enteric neural crest cells leads to a Hirschsprung-like phenotype

    DEFF Research Database (Denmark)

    Breau, Marie A; Pietri, Thomas; Eder, Olivier

    2006-01-01

    crest cells fail to colonise the gut completely, leading to an aganglionosis of the descending colon, which resembles the human Hirschsprung's disease. Moreover, beta1-null enteric neural crest cells form abnormal aggregates in the gut wall, leading to a severe alteration of the ganglia network...... organisation. Organotypic cultures of gut explants reveal that beta1-null enteric neural crest cells show impaired adhesion on extracellular matrix and enhanced intercellular adhesion properties. They display migration defects in collagen gels and gut tissue environments. We also provide evidence that beta1...

  7. Normalization of glenohumeral articular contact pressures after Latarjet or iliac crest bone-grafting.

    Science.gov (United States)

    Ghodadra, Neil; Gupta, Aman; Romeo, Anthony A; Bach, Bernard R; Verma, Nikhil; Shewman, Elizabeth; Goldstein, Jordan; Provencher, Matthew T

    2010-06-01

    Multiple bone-grafting procedures have been described for patients with glenoid bone loss and shoulder instability. The purpose of this study was to investigate the alterations in glenohumeral contact pressure associated with the placement and orientation of Latarjet or iliac crest bone graft augmentation and to compare the amount of glenoid bone reconstruction with two coracoid face orientations. Twelve fresh-frozen cadaver shoulders were tested in static positions of humeral abduction (30 degrees , 60 degrees , and 60 degrees with 90 degrees of external rotation) with a 440-N compressive load. Glenohumeral contact pressure and area were determined sequentially for (1) the intact glenoid; (2) a glenoid with an anterior bone defect involving 15% or 30% of the glenoid surface area; (3) a 30% glenoid defect treated with a Latarjet or iliac crest bone graft placed 2 mm proud, placed flush, or recessed 2 mm in relation to the level of the glenoid; and (4) a Latarjet bone block placed flush and oriented with either the lateral (Latarjet-LAT) or the inferior (Latarjet-INF) surface of the coracoid as the glenoid face. The amount of glenoid bone reconstructed was compared between the Latarjet-LAT and Latarjet-INF conditions. Bone grafts in the flush position restored the mean peak contact pressure to 116% of normal when the iliac crest bone graft was used (p Latarjet-INF bone block was used (p Latarjet-LAT bone block was used (p Latarjet-LAT bone block resulted in mean peak pressures that were significantly higher than those associated with the iliac crest bone graft (p Latarjet-INF bone block (p Latarjet-LAT bone block led to restoration of the glenoid articular contact surface from the 30% defect state to a 5% defect state. Augmentation of the 30% glenoid defect with the Latarjet-INF bone block resulted in complete restoration to the intact glenoid articular surface area. Glenohumeral contact pressure is optimally restored with a flush iliac crest bone graft or with a

  8. Enhancing endothelial progenitor cell for clinical use

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Circulating endothelial progenitor cells (EPCs) havebeen demonstrated to correlate negatively with vascularendothelial dysfunction and cardiovascular risk factors.However, translation of basic research into the clinicalpractice has been limited by the lack of unambiguousand consistent definitions of EPCs and reduced EPCcell number and function in subjects requiring them forclinical use. This article critically reviews the definitionof EPCs based on commonly used protocols, their valueas a biomarker of cardiovascular risk factor in subjectswith cardiovascular disease, and strategies to enhanceEPCs for treatment of ischemic diseases.

  9. EGF–FGF{sub 2} stimulates the proliferation and improves the neuronal commitment of mouse epidermal neural crest stem cells (EPI-NCSCs)

    Energy Technology Data Exchange (ETDEWEB)

    Bressan, Raul Bardini; Melo, Fernanda Rosene; Almeida, Patricia Alves; Bittencourt, Denise Avani; Visoni, Silvia; Jeremias, Talita Silva [Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil); Costa, Ana Paula; Leal, Rodrigo Bainy [Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil); Trentin, Andrea Gonçalves, E-mail: andrea.trentin@ufsc.br [Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil)

    2014-09-10

    Epidermal neural crest stem cells (EPI-NCSCs), which reside in the bulge of hair follicles, are attractive candidates for several applications in cell therapy, drug screening and tissue engineering. As suggested remnants of the embryonic neural crest (NC) in an adult location, EPI-NCSCs are able to generate a wide variety of cell types and are readily accessible by a minimally invasive procedure. Since the combination of epidermal growth factor (EGF) and fibroblast growth factor type 2 (FGF{sub 2}) is mitogenic and promotes the neuronal commitment of various stem cell populations, we examined its effects in the proliferation and neuronal potential of mouse EPI-NCSCs. By using a recognized culture protocol of bulge whiskers follicles, we were able to isolate a population of EPI-NCSCs, characterized by the migratory potential, cell morphology and expression of phenotypic markers of NC cells. EPI-NCSCs expressed neuronal, glial and smooth muscle markers and exhibited the NC-like fibroblastic morphology. The treatment with the combination EGF and FGF{sub 2}, however, increased their proliferation rate and promoted the acquisition of a neuronal-like morphology accompanied by reorganization of neural cytoskeletal proteins βIII-tubulin and nestin, as well as upregulation of the pan neuronal marker βIII-tubulin and down regulation of the undifferentiated NC, glial and smooth muscle cell markers. Moreover, the treatment enhanced the response of EPI-NCSCs to neurogenic stimulation, as evidenced by induction of GAP43, and increased expression of Mash-1 in neuron-like cell, both neuronal-specific proteins. Together, the results suggest that the combination of EGF–FGF2 stimulates the proliferation and improves the neuronal potential of EPI-NCSCs similarly to embryonic NC cells, ES cells and neural progenitor/stem cells of the central nervous system and highlights the advantage of using EGF–FGF{sub 2} in neuronal differentiation protocols. - Highlights: • EPI

  10. Sport’s selection of volley-ball players: morphological and pedagogical criteria of definition of movement endowments: (information 1

    Directory of Open Access Journals (Sweden)

    Leonid Serhiyenko

    2016-02-01

    Full Text Available Purpose: to define methodology of initial sports selection of young volley-ball players. Material & Methods: methods of theoretical analysis and generalization, bibliographic method of search and study of scientific information, a systematic analysis are turned to account in this work. Results: the article deals with the theoretical model of the mast important factors, which define sports endowments of volley-ball players. It is shown the point estimation of body structure and composition, motor and psychomotor abilities, dynamic possibilities, psychophisiological indices in the prognosis of volley-ball players gifted for high sports results. Conclusions: criteria of high movement endowments of volley-ball players are defined; norms of estimation of motor abilities of valley-ball players on the initial steps of sports selection are given.

  11. EXISTENCE THEOREM FOR THE PRICES FIXED POINT PROBLEM OF THE OVERLAPPING GENERATIONS MODEL, VIA METRIC SPACES ENDOWED WITH A GRAPH

    Directory of Open Access Journals (Sweden)

    Magnolia Tilca

    2014-10-01

    Full Text Available The aim of this paper is to study the existence of the solution for the overlapping generations model, using fixed point theorems in metric spaces endowed with a graph. The overlapping generations model has been introduced and developed by Maurice Allais (1947, Paul Samuelson (1958, Peter Diamond (1965 and so on. The present paper treats the case presented by Edmond (2008 in (Edmond, 2008 for a continuous time. The theorem of existence of the solution for the prices fixed point problem derived from the overlapping generations model gives an approximation of the solution via the graph theory. The tools employed in this study are based on applications of the Jachymski fixed point theorem on metric spaces endowed with a graph (Jachymski, 2008

  12. Making headway: the roles of Hox genes and neural crest cells in craniofacial development.

    Science.gov (United States)

    Trainor, Paul A

    2003-04-14

    Craniofacial development is an extraordinarily complex process requiring the orchestrated integration of multiple specialized tissues such as the surface ectoderm, neural crest, mesoderm, and pharyngeal endoderm in order to generate the central and peripheral nervous systems, axial skeleton, musculature, and connective tissues of the head and face. How do the characteristic facial structures develop in the appropriate locations with their correct shapes and sizes, given the widely divergent patterns of cell movements that occur during head development? The patterning information could depend upon localized interactions between the epithelial and mesenchymal tissues or alternatively, the developmental program for the characteristic facial structures could be intrinsic to each individual tissue precursor. Understanding the mechanisms that control vertebrate head development is an important issue since craniofacial anomalies constitute nearly one third of all human congenital defects. This review discusses recent advances in our understanding of neural crest cell patterning and the dynamic nature of the tissue interactions that are required for normal craniofacial development.

  13. Genomic diversity and evolution of the head crest in the rock pigeon

    Science.gov (United States)

    Shapiro, Michael D.; Kronenberg, Zev; Li, Cai; Domyan, Eric T.; Pan, Hailin; Campbell, Michael; Tan, Hao; Huff, Chad D.; Hu, Haofu; Vickrey, Anna I.; Nielsen, Sandra C.A.; Stringham, Sydney A.; Hu, Hao; Willerslev, Eske; Gilbert, M. Thomas P.; Yandell, Mark; Zhang, Guojie; Wang, Jun

    2013-01-01

    The geographic origins of breeds and genetic basis of variation within the widely distributed and phenotypically diverse domestic rock pigeon (Columba livia) remain largely unknown. We generated a rock pigeon reference genome and additional genome sequences representing domestic and feral populations. We find evidence for the origins of major breed groups in the Middle East, and contributions from a racing breed to North American feral populations. We identify EphB2 as a strong candidate for the derived head crest phenotype shared by numerous breeds, an important trait in mate selection in many avian species. We also find evidence that this trait evolved just once and spread throughout the species, and that the crest originates early in development by the localized molecular reversal of feather bud polarity. PMID:23371554

  14. Disproportionately severe calcinosis cutis in an 88-year-old patient with CREST syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Buchowski, J.M.; Ahn, N.U.; Ahn, U.M. [Dept. of Orthopaedic Surgery, Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States); McCarthy, E.F. [Dept. of Orthopaedic Surgery, Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States); Dept. of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Mehta, M.B. [Clinical Associates, Good Samaritan Hospital, Baltimore, MD (United States)

    2001-08-01

    An 88-year-old woman with CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasias) presented with hyperglycemia, intravascular depletion, and atrial fibrillation. The patient was found to have unusually severe calcinosis cutis in both legs extending from the knees to the ankles bilaterally, as well as Raynaud's phenomenon, sclerodactyly, and telangiectasias. The patient was normocalcemic and normophosphatemic. Although subcutaneous calcification is often seen with CREST syndrome, this case is unusual in that the area of involvement was much larger than previously described. Furthermore, the amount of calcinosis was disproportionately severe and was the major cause of symptoms and disability compared with the other components of the syndrome. (orig.)

  15. Conditional Short-crested second order waves in shallow water and with superimposed current

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2004-01-01

    For bottom-supported offshore structures like oil drilling rigs and oil production platforms, a deterministic design wave approach is often applied using a regular non-linear Stokes' wave. Thereby, the procedure accounts for non-linear effects in the wave loading but the randomness of the ocean...... wave, given the value of the wave crest at a specific point in time or space. In the present paper a derivation of the expected second order short-crested wave riding on a uniform current is given. The analysis is based on the second order Sharma and Dean shallow water wave theory and the direction...... of the main wind direction can make any direction with the current. Numerical results showing the importance of the water depth, the directional spreading and the current on the conditional mean wave profile and the associated wave kinematics are presented. A discussion of the use of the conditional wave...

  16. Conditional short-crested waves in shallow water and with superimposed current

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2002-01-01

    For bottom-supported offshore structures like oil drilling rigs and oil production platforms, a deterministic design wave approach is often applied using a regular non-linear Stokes´ wave. Thereby, the procedure accounts for non-linear effects in the wave loading but the randomness of the ocean...... wave, given the value of the wave crest at a specific point in time or space. In the present paper a derivation of the expected linear short-crested wave riding on a uniform current is given. The analysis is based on the conventional shallow water Airy wave theory and the direction of the main wind...... direction can make any direction with the current. A consistent derivation of the wave spectrum taking into account current and finite water depth is used. The numerical results show a significant effect of the water depth, the directional spreading and the current on the conditional mean wave profile...

  17. Implant-Prosthetic Rehabilitation in Bilateral Agenesis of Maxillary Lateral Incisors with a Mini Split Crest

    Directory of Open Access Journals (Sweden)

    M. M. Figliuzzi

    2016-01-01

    Full Text Available The reported clinical case describes the surgical procedure of ridge augmentation by using a “split crest” technique with a partial thickness flap and a subsequent implant-prosthetic rehabilitation aimed at treating a bilateral agenesis of the upper lateral incisors. In such cases with vestibule-palatal and mesial-distal scarce bone thicknesses associated with the need of a proper functional and aesthetic rehabilitation, the split crest technique is particularly suitable. In the case we reported, because of the poor bone thicknesses, we performed a minimally invasive split crest which allowed a correct insertion of the fixtures. This technique allowed us to achieve an optimal functional and aesthetic rehabilitation; moreover, we obtained a good emergency profile, ensuring the vitality of the close teeth and ensuring a good primary stability and the following osseointegration of dental implants.

  18. Linear surface capillary-gravity short-crested waves on a current

    Institute of Scientific and Technical Information of China (English)

    HUANG Hu

    2008-01-01

    One of the forward situations in the study of water waves is the basic three-dimensional surface wave motion of short-crested waves. Capillary waves result in rich effects concerned closely with remote sensing in the open ocean. Ocean currents experience a complete process in surface wave motion. Based on the above ideas, a linear dynamical system of surface capillary-gravity short-crested waves is developed by considering the current effects, thus leading to the following analytical expressions of the kinematic and dynamic variables: the wave height, the wave steepness, the phase velocity, the wave-particle velocities, accelerations and trajectories and the wave pressure. A number of the classi-cal, typical and latest special wave cases can arise from these expressions.

  19. Conditional Short-crested second order waves in shallow water and with superimposed current

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2004-01-01

    wave, given the value of the wave crest at a specific point in time or space. In the present paper a derivation of the expected second order short-crested wave riding on a uniform current is given. The analysis is based on the second order Sharma and Dean shallow water wave theory and the direction......For bottom-supported offshore structures like oil drilling rigs and oil production platforms, a deterministic design wave approach is often applied using a regular non-linear Stokes' wave. Thereby, the procedure accounts for non-linear effects in the wave loading but the randomness of the ocean...... waves is poorly represented, as the shape of the wave spectrum does not enter the wave kinematics. To overcome this problem and still keep the simplicity of a deterministic approach, Tromans, Anaturk and Hagemeijer (1991) suggested the use of a deterministic wave, defined as the expected linear Airy...

  20. Signi fi cance of Neural Crest in Tooth Development: The Molecular Signature

    Directory of Open Access Journals (Sweden)

    VP Jayasekharan

    2014-07-01

    Full Text Available The neural crest originates from cells located along the lateral margins of the neural plate. Neural crest cells arise as the result of an inductive action by the non-neural ectoderm adjacent to the neural plate and possibly by nearby mesoderm as well. As the neural tube forms, a group of cells separate from the neuro- ectoderm. These cells have the capacity to migrate and differen- tiate extensively within the developing embryo and they are the basis of structures such as spinal sensory ganglia, sympathetic neurons, Schwann cells, pigment cells and meninges. Speci fi c interactions occur during the development of tooth and recent research has concentrated more on the molecular aspects of these interactions. Thus, it is highly imperative to understand and digress the complex mechanisms involved in these processes

  1. 75 FR 34488 - National Endowment for the Arts; National Council on the Arts 170th Meeting; Correction

    Science.gov (United States)

    2010-06-17

    ... ARTS AND THE HUMANITIES National Endowment for the Arts; National Council on the Arts 170th Meeting... the Arts. The meeting will be held on June 24-25, 2010 not June 24-25, 2009, in Rooms 527 and M-09 at..., from 12:30 p.m.-2 p.m. on June 24th, will be closed for National Medal of Arts review...

  2. Maximal Sobolev regularity for solutions of elliptic equations in infinite dimensional Banach spaces endowed with a weighted Gaussian measure

    Science.gov (United States)

    Cappa, G.; Ferrari, S.

    2016-12-01

    Let X be a separable Banach space endowed with a non-degenerate centered Gaussian measure μ. The associated Cameron-Martin space is denoted by H. Let ν =e-U μ, where U : X → R is a sufficiently regular convex and continuous function. In this paper we are interested in the W 2 , 2 regularity of the weak solutions of elliptic equations of the type

  3. Design and synthesis of benzimidazole analogs endowed with oxadiazole as selective COX-2 inhibitor.

    Science.gov (United States)

    Rathore, Ankita; Rahman, Mujeeb Ur; Siddiqui, Anees Ahamad; Ali, Abuzer; Shaharyar, Mohammad

    2014-12-01

    New molecules of benzimidazole endowed with oxadiazole were designed and synthesized from 2-(2-((pyrimidin-2-ylthio)methyl)-1H-benzo[d]imidazol-1-yl)acetohydrazide as 1-((5-substituted alkyl/aryl-1,3,4-oxadiazol-2-yl)methyl)-2-((pyrimidin-2-ylthio)methyl)-1H-benzimidazoles (5a-r) with the aim to acquire selective cyclooxygenase (COX-2) inhibitor activity. The synthesized compounds were screened by in vitro cyclooxygenase assays to determine COX-1 and COX-2 inhibitory potency and the results showed that they had good-to-remarkable activity with an IC50 range of 11.6-56.1 µM. The most active compounds were further screened for their in vivo anti-inflammatory activity by using the carrageenan-induced rat paw edema model. In vitro anticancer activities of the hybrid compounds were assessed by the National Cancer Institute (NCI), USA, against 60 human cell lines, and the results showed a good spectrum. Compound 5l exhibited significant COX-2 inhibition with an IC50 value of 8.2 µM and a percent protection of 68.4%. Compound 5b evinced moderate cytotoxicity toward the UO-31 cell line of renal cancer. A docking study was performed using Maestro 9.0, to provide the binding mode into the binding sites of the cyclooxygenase enzyme. Hopefully, in the future, compound 5l could serve as a lead compound for developing new COX-2 inhibitors.

  4. AHAS herbicide resistance endowing mutations: effect on AHAS functionality and plant growth.

    Science.gov (United States)

    Yu, Qin; Han, Heping; Vila-Aiub, Martin M; Powles, Stephen B

    2010-09-01

    Twenty-two amino acid substitutions at seven conserved amino acid residues in the acetohydroxyacid synthase (AHAS) gene have been identified to date that confer target-site resistance to AHAS-inhibiting herbicides in biotypes of field-evolved resistant weed species. However, the effect of resistance mutations on AHAS functionality and plant growth has been investigated for only a very few mutations. This research investigates the effect of various AHAS resistance mutations in Lolium rigidum on AHAS functionality and plant growth. The enzyme kinetics of AHAS from five purified L. rigidum populations, each homozygous for the resistance mutations Pro-197-Ala, Pro-197-Arg, Pro-197-Gln, Pro-197-Ser or Trp-574-Leu, were characterized and the pleiotropic effect of three mutations on plant growth was assessed via relative growth rate analysis. All these resistance mutations endowed a herbicide-resistant AHAS and most resulted in higher extractable AHAS activity, with no-to-minor changes in AHAS kinetics. The Pro-197-Arg mutation slightly (but significantly) increased the K(m) for pyruvate and remarkably increased sensitivity to feedback inhibition by branched chain amino acids. Whereas the Pro-197-Ser and Trp-574-Leu mutations exhibited no significant effects on plant growth, the Pro-197-Arg mutation resulted in lower growth rates. It is clear that, at least in L. rigidum, these five AHAS resistance mutations have no major impact on AHAS functionality and hence probably no plant resistance costs. These results, in part, explain why so many Pro-197 AHAS resistance mutations in AHAS have evolved and why the Pro-197-Ser and the Trp-574-Leu AHAS resistance mutations are frequently found in many weed species.

  5. Fostering creativity: how the Duke Graduate Medical Education Quasi-Endowment encourages innovation in GME.

    Science.gov (United States)

    Andolsek, Kathryn M; Murphy, Gwendolyn; Nagler, Alisa; Moore, Peggy R; Schlueter, Joanne; Weinerth, John L; Cuffe, Michael S; Dzau, Victor J

    2013-02-01

    The Duke Medicine Graduate Medical Education Quasi-Endowment, established in 2006, provides infrastructure support and encourages educational innovation. The authors describe Duke's experience with the "grassroots innovation" part of the fund, the Duke Innovation Fund, and discuss the Innovation Fund's processes for application, review, and implementation, and also outcomes, impact, and intended and unintended consequences.In the five years of the Innovation Fund described (2007-2011), 105 projects have been submitted, and 78 have been funded. Thirty-seven projects have been completed. Approved funding ranged from $2,363 to $348,750, with an average award of $66,391. This represents 42% of funding originally requested. Funding could be requested for a period of 6 months to 3 years. The average duration of projects was 27 months, with a range from 6 months to 36 months. Eighty percent of projects were completed on time. Two projects were closed because of lack of progress and failure to adhere to reporting requirements. Thirty-nine are ongoing.Program directors report great success in meeting project outcomes and concrete impacts on resident and faculty attitudes and performance. Ninety-two percent report that their projects would have never been accomplished without this funding. Projects have resulted in at least 68 posters, abstracts, and peer-reviewed presentations. At least 12 peer-reviewed manuscripts were published.There has been tremendous diversity of projects; all 13 clinical departments have been represented. Interdepartmental and intradepartmental program cooperation has increased. This modest seed money has resulted in demonstrable sustainable impacts on teaching and learning, and increased morale and scholarly recognition.

  6. Double-crested Cormorant Diet Composition from Two Colonies in Saginaw Bay, Lake Huron, 2013-2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set contains information about the diets of double-crested cormorants (Phalacrocorax auritus) collected from Saginaw Bay, Lake Huron during...

  7. What Crested Butte Mountain Resort Feels the Ski Industry Is, In General, Looking for in College Graduates.

    Science.gov (United States)

    Jernigan, Rick

    This paper describes general employment requirements for employment candidates in the skiing industry, as seen by Crested Butte Mountain Resort personnel. General educational requirements are primarily business skills, including: communications, computers, math, finance, accounting, economics, personnel administration, and psychology. Other…

  8. Laboratory Research on Effective Test Area of Short-Crested Waves Generated by Two-Sided Segmented Wavemakers

    Institute of Scientific and Technical Information of China (English)

    李俊; 陈刚; 杨建民; 彭涛

    2014-01-01

    The size and shape of the effective test area are crucial to consider when short-crested waves are created by segmented wavemakers. The range of the effective test area of short-crested waves simulated by two-sided segmented wavemakers is analyzed in this paper. The experimental investigation on the wave field distribution of short-crested waves generated by two-sided segmented wavemakers is conducted by using an array of wave gauges. Wave spectra and directional spreading function are analyzed and the results show that when the main direction is at a certain angle with the normal line of wave generators, the wave field of 3D short-crested waves generated by two-sided segmented wavemakers has good spatial uniformity within the model test area. The effective test area can provide good wave environments for seakeeping model tests of various ocean engineering structures in the deep ocean engineering basin.

  9. The double-crested cormorant in Lake Michigan: A review of population trends, ecology and current management

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Double-crested Cormorant, or DCCO, is the most widely distributed cormorant of the six North American cormorant species. This work is an attempt to review and...

  10. Theoretical Investigation of Peak-Delay Force Reduction for Caissons Exposed to Non-breaking Short-Crested Waves

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Z.

    In nature coastal structures are exposed to oblique short-crested waves. The effect of wave incident angle on total wave force on a long caisson are twofold. The one is the force reduction due to the reduction of instantaneous point pressure on the caisson, named point-pressure force reduction...... on the peak-delay force reduction of caissons exposed to non-breaking short-crested waves. Battjes (1982) has investigated theoretically the peak-delay force reduction of shortcrested waves with only one frequency component. Such a force reduction factor cannot be applied because in nature waves are composed...... of many linear components with various frequencies. In this paper the peak-delay force reduction factor is defined on basis of zero-moment of the force spectrum. Based on linear wave theory, formulae for calculation of peakdelay force reduction factor for linear, long-crested and short-crested non-breaking...

  11. Foxc1 and Foxc2 in the Neural Crest Are Required for Ocular Anterior Segment Development

    Science.gov (United States)

    Seo, Seungwoon; Chen, Lisheng; Liu, Wenzhong; Zhao, Demin; Schultz, Kathryn M.; Sasman, Amy; Liu, Ting; Zhang, Hao F.; Gage, Philip J.; Kume, Tsutomu

    2017-01-01

    Purpose The large Forkhead (Fox) transcription factor family has essential roles in development, and mutations cause a wide range of ocular and nonocular disease. One member, Foxc2 is expressed in neural crest (NC)-derived periocular mesenchymal cells of the developing murine eye; however, its precise role in the development, establishment, and maintenance of the ocular surface has yet to be investigated. Methods To specifically delete Foxc2 from NC-derived cells, conditional knockout mice for Foxc2 (NC-Foxc2−/−) were generated by crossing Foxc2F mice with Wnt1-Cre mice. Similarly, we also generated compound NC-specific mutations of Foxc2 and a closely related gene, Foxc1 (NC-Foxc1−/−;NC-Foxc2−/−) in mice. Results Neural crest-Foxc2−/− mice show abnormal thickness in the peripheral-to-central corneal stroma and limbus and displaced pupils with irregular iris. The neural crest-specific mutation in Foxc2 also leads to ectopic neovascularization in the cornea, as well as impaired ocular epithelial cell identity and corneal conjunctivalization. Compound, NC-specific Foxc1; Foxc2 homozygous mutant mice have more severe defects in structures of the ocular surface, such as the cornea and eyelids, accompanied by significant declines in the expression of another key developmental factor, Pitx2, and its downstream effector Dkk2, which antagonizes canonical Wnt signaling. Conclusions The neural crest-Foxc2 mutation is associated with corneal conjunctivalization, ectopic corneal neovascularization, and disrupted ocular epithelial cell identity. Furthermore, Foxc2 and Foxc1 cooperatively function in NC-derived mesenchymal cells to ensure proper morphogenesis of the ocular surface via the regulation of Wnt signaling. Together, Foxc2 is required in the NC lineage for mesenchymal-epithelial interactions in corneal and ocular surface development. PMID:28253399

  12. The iliac crest in forensic age diagnostics: evaluation of the apophyseal ossification in conventional radiography.

    Science.gov (United States)

    Wittschieber, Daniel; Vieth, Volker; Domnick, Christoph; Pfeiffer, Heidi; Schmeling, Andreas

    2013-03-01

    Due to the increasing significance of forensic age estimations in the age of globalisation, novel radiographic criteria besides clavicles and hand bones may provide additional certainty for forensic age expertises. The present study analyses the suitability of the iliac crest apophysis by means of 643 pelvic radiographs of patients between 10 and 30 years of age. Retrospective assessments were carried out according to the forensically established classification and sub-classification systems modified after Kreitner et al. (Rofo 166(6):481-486, 1997) and Kellinghaus et al. (Int J Legal Med 124(4):321-325, 2010). The basic ossification stages range from 1 to 4, and the sub-stages of stage 2 and 3 range from a to c. While stage 3c was first achieved at the age of 15 by both sexes, stage 4 was first observed in females at the age of 16 and in males at the age of 17. This indicates the possibility of a valid diagnosis of both the age of 14 and the age of 16 years which represent legally relevant age thresholds in numerous countries. Applied as targeted radiography on the iliac crest, the exposure to radiation would range between other radiographic techniques recently applied. Therefore, the iliac crest apophysis appears principally suitable as novel possible criterion for forensic age estimation in the living. However, for the establishment of the iliac crest apophysis in routine diagnostics, further studies are needed focussing on the comparison of different grading systems and different radiological techniques.

  13. Cell Motility and Invasiveness of Neurofibromin-Deficient Neural Crest Cells and Malignant Triton Tumor Lines

    Science.gov (United States)

    2005-06-01

    immunoblotting techniques to characterize signaling pathways activated by TGF-beta and PDGF-BB in MPNST -like sarcoma cell lines isolated from cisNfl+/-;p53...mouse model to include characterizations of genomic instability in the context of malignant transformation, and to test possible modifiers of MPNST ...growth and invasiveness. 15. SUBJECT TERMS neurofibromatosis type 1; neural crest cells; cell motility and Migration; PDGF; TGF-beta; MPNST

  14. New Results from the NOAA CREST Lidar Network (CLN Observations in the US Eastcoast

    Directory of Open Access Journals (Sweden)

    Moshary Fred

    2016-01-01

    Full Text Available This paper presents coordinated ground-based observations by the NOAA-CREST Lidar Network (CLN for profiling of aerosols, cloud, water vapor, and wind along the US east coast including Caribbean region at Puerto Rico. The instrumentation, methodology and observation capability are reviewed. The applications to continental and intercontinental-scale transport of smoke and dust plumes, and their large scale regional impact are discussed.

  15. Crest lines extraction in volume 3D medical images : a multi-scale approach

    OpenAIRE

    Monga, Olivier; Lengagne, Richard; Deriche, Rachid

    1994-01-01

    Projet SYNTIM; Recently, we have shown that the differential properties of the surfaces represented by 3D volumic images can be recovered using their partial derivatives. For instance, the crest lines can be characterized by the first, second and third partial derivatives of the grey level function $I(x,y,z)$. In this paper, we show that~: - the computation of the partial derivatives of an image can be improved using recursive filters which approximate the Gaussian filter, - a multi-scale app...

  16. Neural crest contribution to lingual mesenchyme, epithelium and developing taste papillae and taste buds

    OpenAIRE

    Liu, Hong-Xiang; Komatsu, Yoshihiro; Mishina, Yuji; Mistretta, Charlotte M.

    2012-01-01

    The epithelium of mammalian tongue hosts most of the taste buds that transduce gustatory stimuli into neural signals. In the field of taste biology, taste bud cells have been described as arising from “local epithelium”, in distinction from many other receptor organs that are derived from neurogenic ectoderm including neural crest (NC). In fact, contribution of NC to both epithelium and mesenchyme in the developing tongue is not fully understood. In the present study we used two independent, ...

  17. Leader cells define directionality of trunk, but not cranial, neural crest migration

    OpenAIRE

    Richardson, Jo; Gauert, Anton; Montecinos, Luis Briones; Fanlo, Lucía; Alhashem, Zainalabdeen Mohmammed; Assar, Rodrigo; MARTI, ELISA; Kabla, Alexandre; Härtel, Steffen; Linker, Claudia

    2016-01-01

    Summary:Collective cell migration is fundamental for life and a hallmark of cancer. Neural crest (NC) cells migrate collectively, but the mechanisms governing this process remain controversial. Previous analyses in Xenopus indicate that cranial NC (CNC) cells are a homogeneous population relying on cell-cell interactions for directional migration, while chick embryo analyses suggest a heterogeneous population with leader cells instructing directionality. Our data in chick and zebrafish embryo...

  18. Traumatic lumbar hernia repair: a laparoscopic technique for mesh fixation with an iliac crest suture anchor.

    Science.gov (United States)

    Links, D J R; Berney, C R

    2011-12-01

    Traumatic lumbar hernia (TLH) is a rare presentation. Traditionally, these have been repaired via an open approach. Recurrence can be a problem due to the often limited tissue available for mesh fixation at the inferior aspect of the hernia defect. We report the successful use of bone suture anchors placed in the iliac crest during transperitoneal laparoscopy for mesh fixation to repair a recurrent TLH. This technique may be particularly useful after previous failed attempts at open TLH repair.

  19. Computed tomography evaluation of the iliac crest apophysis: age estimation in living individuals.

    Science.gov (United States)

    Ekizoglu, Oguzhan; Inci, Ercan; Erdil, Irem; Hocaoglu, Elif; Bilgili, Mustafa Gokhan; Kazimoglu, Cemal; Reisoglu, Ali; Can, Ismail Ozgur

    2016-07-01

    Determination of the ossification properties of the iliac apophysis is important not only in the clinical evaluation of patients undergoing orthopedic surgery but also in age estimation studies for forensic purposes. The literature includes both anthropological and radiological (conventional radiography, ultrasonography, and magnetic resonance imaging modalities) investigations of the different staging systems used for these purposes. In this study, we assessed the utility of computed tomography (CT) of the iliac crest apophysis in estimating forensic age. CT scans of the iliac crest apophysis of 380 patients (187 females, 193 males, and 10-29 years of age) were evaluated according to the four-stage system. Further subclassification did not give data properly due to the reference length measurement of the iliac wing with CT. Thus, in our series, stage 2 was first seen in 12 years of age and stage 3 in those 14 years of age in both sexes and on both sides of the pelvis. Stage 4 was first seen in 17 years of both sexes but only on the right side; on the left side, it appeared in females 18 years of age and in males 17 years of age. Present data was found consistent with previous pelvic radiographic findings. First seen ages for stage 2 and 3 are 12 and 14 years respectively which presented valuable information for legally important age thresholds. However, disadvantages of CT, including high-dose radiation exposure to gonads, the difficulty of evaluating the iliac crest, and the age boundary of 17 years, could make this method infeasible, as compared with hand wrist and pelvic radiographic methods. CT of the iliac crest has probably a greater utility where preexisting CT scans of the pelvic region are available, and it may be considered as a supportive method for age-estimation purposes.

  20. Estimation of Overtopping Rates on Slopes in Wave Power Devices and Other Low Crested Structures

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Burcharth, Hans Falk

    2002-01-01

    Motivated by questions raised by developers of wave energy devices based on wave overtopping concepts, model tests have been performed to study overtopping of structures with limited draught, low crest freeboards and slope geometries designed to increase overtopping and thereby also the captured ...... amount of wave energy. The test results have been incorporated in an existing overtopping prediction formula by application of correction factors presented in the paper...

  1. The progenitors of supernovae Type Ia

    Science.gov (United States)

    Toonen, Silvia

    2014-09-01

    Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. SNeIa are generally thought to be thermonuclear explosions of carbon/oxygen (CO) white dwarfs (WDs). The canonical scenarios involve white dwarfs reaching the Chandrasekhar mass, either by accretion from a non-degenerate companion (single-degenerate channel, SD) or by a merger of two CO WDs (double-degenerate channel, DD). The study of SNeIa progenitors is a very active field of research for binary population synthesis (BPS) studies. The strength of the BPS approach is to study the effect of uncertainties in binary evolution on the macroscopic properties of a binary population, in order to constrain binary evolutionary processes. I will discuss the expected SNeIa rate from the BPS approach and the uncertainties in their progenitor evolution, and compare with current observations. I will also discuss the results of the POPCORN project in which four BPS codes were compared to better understand the differences in the predicted SNeIa rate of the SD channel. The goal of this project is to investigate whether differences in the simulated populations are due to numerical effects or whether they can be explained by differences in the input physics. I will show which assumptions in BPS codes affect the results most and hence should be studied in more detail.

  2. Single degenerate supernova type Ia progenitors

    CERN Document Server

    Bours, M C P; Nelemans, G

    2013-01-01

    There is general agreement that supernovae Ia correspond to the thermonuclear runaway of a white dwarf that is part of a compact binary, but the details of the progenitor systems are still unknown and much debated. One of the proposed progenitor theories is the single-degenerate channel in which a white dwarf accretes from a companion, grows in mass, reaches a critical mass limit, and is then consumed after thermonuclear runaway sets in. However, there are major disagreements about the theoretical delay time distribution and the corresponding time-integrated supernova Ia rate from this channel. We investigate whether the differences are due to the uncertainty in the common envelope phase and the fraction of transferred mass that is retained by the white dwarf. This so-called retention efficiency may have a strong influence on the final amount and timing of supernovae Ia. Using the population synthesis code SeBa, we simulated large numbers of binaries for various assumptions on common envelopes and retention e...

  3. Galactic Constraints on Supernova Progenitor Models

    CERN Document Server

    Acharova, I; Mishurov, Yu; Kovtyukh, V

    2013-01-01

    We undertake a statistical analysis of the radial abundance distributions in the Galactic disk within a theoretical framework for Galactic chemical evolution which incorporates the influence of spiral arms. 1) The mean mass of oxygen ejected per core-collapse SNe (CC SNe) event (which are concentrated within spiral arms) is $\\sim$0.27 M$_{\\odot}$; 2) the mean mass of iron ejected by `tardy' Type Ia SNe (SNeIa; progenitors of whom are older/longer-lived stars with ages $\\simgt$100 Myr and up to several Gyr, which do not concentrate within spiral arms) is $\\sim$0.58 M$_{\\odot}$; 3) the upper mass of iron ejected by prompt SNeIa (SNe whose progenitors are younger/shorter-lived stars with ages $\\simlt$100 Myr, which are concentrated within spiral arms) is $\\leq$0.23 M$_{\\odot}$ per event; 4) the corresponding mean mass of iron produced by CC SNe is $\\leq$0.04 M$_{\\odot}$ per event; (v) short-lived SNe (core-collapse or prompt SNeIa) supply $\\sim$85% of the Galactic disk's iron. The inferred low mean mass of oxyge...

  4. Magnetized massive stars as magnetar progenitors

    CERN Document Server

    Hu, Ren-Yu

    2009-01-01

    The origin of ultra-intense magnetic fields on magnetars is a mystery in modern astrophysics. We model the core collapse dynamics of massive progenitor stars with high surface magnetic fields in the theoretical framework of a self-similar general polytropic magnetofluid under the self-gravity with a quasi-spherical symmetry. With the specification of physical parameters such as mass density, temperature, magnetic field and wind mass loss rate on the progenitor stellar surface and the consideration of a rebound shock breaking through the stellar interior and envelope, we find a remnant compact object (i.e. neutron star) left behind at the centre with a radius of $\\sim 10^6$ cm and a mass range of $\\sim 1-3$ solar masses. Moreover, we find that surface magnetic fields of such kind of compact objects can be $\\sim 10^{14}-10^{15}$ G, consistent with those inferred for magnetars which include soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars (AXPs). The magnetic field enhancement factor critically depend...

  5. Endothelial Progenitor Cells Enter the Aging Arena.

    Directory of Open Access Journals (Sweden)

    Kate eWilliamson

    2012-02-01

    Full Text Available Age is a significant risk factor for the development of vascular diseases, such as atherosclerosis. Although pharmacological treatments, including statins and anti-hypertensive drugs, have improved the prognosis for patients with cardiovascular disease, it remains a leading cause of mortality in those aged 65 years and over. Furthermore, given the increased life expectancy of the population in developed countries, there is a clear need for alternative treatment strategies. Consequently, the relationship between aging and progenitor cell-mediated repair is of great interest. Endothelial progenitor cells (EPCs play an integral role in the cellular repair mechanisms for endothelial regeneration and maintenance. However, EPCs are subject to age-associated changes that diminish their number in circulation and function, thereby enhancing vascular disease risk. A great deal of research is aimed at developing strategies to harness the regenerative capacity of these cells.In this review, we discuss the current understanding of the cells termed ‘EPCs’, examine the impact of age on EPC-mediated repair and identify therapeutic targets with potential for attenuating the age-related decline in vascular health via beneficial actions on EPCs.

  6. Retinal progenitor cell xenografts to the pig retina

    DEFF Research Database (Denmark)

    Warfvinge, Karin; Kiilgaard, Jens Folke; Lavik, Erin B;

    2005-01-01

    To investigate the survival, integration, and differentiation of mouse retinal progenitor cells after transplantation to the subretinal space of adult pigs.......To investigate the survival, integration, and differentiation of mouse retinal progenitor cells after transplantation to the subretinal space of adult pigs....

  7. Progenitor cells in arteriosclerosis: good or bad guys?

    Science.gov (United States)

    Campagnolo, Paola; Wong, Mei Mei; Xu, Qingbo

    2011-08-15

    Accumulating evidence indicates that the mobilization and recruitment of circulating or tissue-resident progenitor cells that give rise to endothelial cells (ECs) and smooth muscle cells (SMCs) can participate in atherosclerosis, neointima hyperplasia after arterial injury, and transplant arteriosclerosis. It is believed that endothelial progenitor cells do exist and can repair and rejuvenate the arteries under physiologic conditions; however, they may also contribute to lesion formation by influencing plaque stability in advanced atherosclerotic plaque under specific pathologic conditions. At the same time, smooth muscle progenitors, despite their capacity to expedite lesion formation during restenosis, may serve to promote atherosclerotic plaque stabilization by producing extracellular matrix proteins. This profound evidence provides support to the hypothesis that both endothelial and smooth muscle progenitors may act as a double-edged sword in the pathogenesis of arteriosclerosis. Therefore, the understanding of the regulatory networks that control endothelial and smooth muscle progenitor differentiation is undoubtedly fundamental both for basic research and for improving current therapeutic avenues for atherosclerosis. We update the progress in progenitor cell study related to the development of arteriosclerosis, focusing specifically on the role of progenitor cells in lesion formation and discuss the controversial issues that regard the origins, frequency, and impact of the progenitors in the disease.

  8. Sox10-dependent neural crest origin of olfactory microvillous neurons in zebrafish.

    Science.gov (United States)

    Saxena, Ankur; Peng, Brian N; Bronner, Marianne E

    2013-03-19

    The sense of smell in vertebrates is detected by specialized sensory neurons derived from the peripheral nervous system. Classically, it has been presumed that the olfactory placode forms all olfactory sensory neurons. In contrast, we show that the cranial neural crest is the primary source of microvillous sensory neurons within the olfactory epithelium of zebrafish embryos. Using photoconversion-based fate mapping and live cell tracking coupled with laser ablation, we followed neural crest precursors as they migrated from the neural tube to the nasal cavity. A subset that coexpressed Sox10 protein and a neurogenin1 reporter ingressed into the olfactory epithelium and differentiated into microvillous sensory neurons. Timed loss-of-function analysis revealed a critical role for Sox10 in microvillous neurogenesis. Taken together, these findings directly demonstrate a heretofore unknown contribution of the cranial neural crest to olfactory sensory neurons in zebrafish and provide important insights into the assembly of the nascent olfactory system. DOI:http://dx.doi.org/10.7554/eLife.00336.001.

  9. EXTRACTION, QUANTIFICATION, AND MOLAR MASS DETERMINATION OF HYALURONIC ACID EXTRACTED FROM CHICKEN CREST

    Directory of Open Access Journals (Sweden)

    C. S. ROSA

    2008-11-01

    Full Text Available

    Hyaluronic acid (HA is part of the connective tissue. The polymer is composed of alternating units of ß-d-glucuronic acid and N-acetyl-ß-d-glucosamine linked, respectively, via 1-3 and 1-4 bonds. The chicken crest is one of the richest tissues in this polysaccharide. Since Brazil is one of the main chicken exporters in the world, the utilization of the crests of abated animals for the HA obtaining is particularly attractive. The present work sought to extract HA from chicken crest and to determine the molar mass of the extracted acid. Extraction was accomplished by proteolytic digestion with papain during 24 h at 60oC, followed by precipitation with cetylpyridinium chloride (CPC. Hexuronic acid content was determined via the carbazole method, the intrinsic viscosity was measured using the ball viscosimeter, and the molar mass was calculated by extrapolating the calibration line to zero. In addition, qualitative infrared spectroscopy was carried out on the sample using the Bomem MB spectrophotometer. The results show that the extraction method was effective: the extracted acid possesses a large molecular mass, and the extract contains a signifi cant amount of HA.

  10. Evaluating 3D registration of CT-scan images using crest lines

    Science.gov (United States)

    Ayache, Nicholas; Gueziec, Andre P.; Thirion, Jean-Philippe; Gourdon, A.; Knoplioch, Jerome

    1993-06-01

    We consider the issue of matching 3D objects extracted from medical images. We show that crest lines computed on the object surfaces correspond to meaningful anatomical features, and that they are stable with respect to rigid transformations. We present the current chain of algorithmic modules which automatically extract the major crest lines in 3D CT-Scan images, and then use differential invariants on these lines to register together the 3D images with a high precision. The extraction of the crest lines is done by computing up to third order derivatives of the image intensity function with appropriate 3D filtering of the volumetric images, and by the 'marching lines' algorithm. The recovered lines are then approximated by splines curves, to compute at each point a number of differential invariants. Matching is finally performed by a new geometric hashing method. The whole chain is now completely automatic, and provides extremely robust and accurate results, even in the presence of severe occlusions. In this paper, we briefly describe the whole chain of processes, already presented to evaluate the accuracy of the approach on a couple of CT-scan images of a skull containing external markers.

  11. Applications of Mesenchymal Stem Cells and Neural Crest Cells in Craniofacial Skeletal Research

    Directory of Open Access Journals (Sweden)

    Satoru Morikawa

    2016-01-01

    Full Text Available Craniofacial skeletal tissues are composed of tooth and bone, together with nerves and blood vessels. This composite material is mainly derived from neural crest cells (NCCs. The neural crest is transient embryonic tissue present during neural tube formation whose cells have high potential for migration and differentiation. Thus, NCCs are promising candidates for craniofacial tissue regeneration; however, the clinical application of NCCs is hindered by their limited accessibility. In contrast, mesenchymal stem cells (MSCs are easily accessible in adults, have similar potential for self-renewal, and can differentiate into skeletal tissues, including bones and cartilage. Therefore, MSCs may represent good sources of stem cells for clinical use. MSCs are classically identified under adherent culture conditions, leading to contamination with other cell lineages. Previous studies have identified mouse- and human-specific MSC subsets using cell surface markers. Additionally, some studies have shown that a subset of MSCs is closely related to neural crest derivatives and endothelial cells. These MSCs may be promising candidates for regeneration of craniofacial tissues from the perspective of developmental fate. Here, we review the fundamental biology of MSCs in craniofacial research.

  12. Free iliac crest grafts with periosteum for treatment of old acetabular defects

    Institute of Scientific and Technical Information of China (English)

    ZHAO De-wei; SUN Qiang; WANG Ben-jie; CUI Da-ping

    2006-01-01

    Objective: To inquire into the therapeutic effectiveness of free iliac crest grafts with periosteum on old acetabular defects.Methods: From February 1996 to June 2005, 9 patients were treated with free iliac crest grafts with periosteum to reconstruct old acetabular defects. There were 7 males and 2 females and the average age was 41.3 years. The acetabular defects were caused by traffic accidents in 6 cases and fall injury in 3 cases. The time from injury to treatment was 4-13 months and averaged 8 months. Intraoperatively we firstly removed the acetabular fracture fragments of the posterior wall. The femoral head was then reducted. Bone graft was harvested from the iliac crest with periosteum, which was sculpted with a rongeur to conform to the defect. The concave (iliac fossa) side of the graft was placed toward the femoral head. The graft was securedly fixed by two to three leg screws.Results: Postoperative syndrome was not found in any of the cases. Harris' score system showed that the score raised from 32. 3 points preoperatively to 81 points postoperatively. The hip function was evaluated as excellent in 3 cases, good in 4 cases and fair in 2 cases.Conclusions: Although this procedure could not exactly reproduce the anatomy of the hip joint, it enables to restore the posterior stability, provide bone-stock for the hip joints and prevent dislocation of the femoral head.

  13. Involvement of endothelin receptors in normal and pathological development of neural crest cells.

    Science.gov (United States)

    Pla, Patrick; Larue, Lionel

    2003-06-01

    Endothelin receptors (Ednr) are G-protein-coupled receptors with seven membrane-spanning domains and are involved in various physiological processes in adults. We review here the function of these receptors during the development and transformation of the neural crest cell-specific lineage. Neural crest cells (NCC) may be classified according to their location in the body. In particular, there are clear differences between the neural crest cells arising from the cephalic part of the embryo and those arising from the vagal and truncal part. The development of cranial and cardiac NCC requires the endothelin-1/Ednra system to be fully functional whereas the development of more posterior NCC requires full functionality of the endothelin-3/Ednrb system. Mutations have been found in the genes corresponding to these systems in mammals. These mutations principally impair pigmentation and enteric ganglia development. The precise patterns of expression of these receptors and their ligands have been determined in avian and mammalian models. Data obtained in vitro and in vivo have provided insight into the roles of these proteins in cell proliferation, migration, differentiation and transformation.

  14. Reconstruction of large iliac crest defects after graft harvest using autogenous rib graft: a prospective controlled study.

    Science.gov (United States)

    Bapat, Mihir R; Chaudhary, Kshitij; Garg, Hitesh; Laheri, Vinod

    2008-11-01

    Prospective controlled study analyzing the donor site morbidity after reconstruction of full thickness iliac crest defects, using autologous rib grafts. To compare the pain and cosmetic outcomes of patients with iliac crest reconstruction with those who have had no reconstruction of the iliac crest. Chronic donor site pain and poor cosmesis have been the major deterrents in using iliac crest for long-segment spinal reconstructions. Iliac crest reconstruction with rib has been reported but most studies are uncontrolled and retrospective. Patients with iliac defects rib graft harvested during the anterolateral approach to spine. Rib graft of the appropriate contour was impacted into the notches created in the iliac crest defect. The control group comprised 16 patients without reconstruction of the iliac crest. The pain, cosmesis, and functional disability were assessed on the basis of visual analog scores and a predesigned questionnaire. Judet iliac views were used to assess the incorporation of the rib graft. Evaluation was performed at 1.5, 3, 6, and 12 months, respectively. Intensity and incidence of pain was significantly lower in the reconstructed group. Cosmetic outcome was also significantly better in this group. Patients in control group had significant complications related to the tenting of skin over the defect such as bursitis and skin necrosis. Radiologic incorporation was documented in 95% of patients with 1 patient having resorption of the rib graft. Rib graft reconstruction provides a cheap and effective alternative for iliac crest reconstruction. Patients undergoing thoracotomy or thoraco-phrenico-lumbotomy for spinal reconstruction, the unutilized rib graft should be used to reconstruct the iliac defect. Reduced donor site morbidity and better cosmesis are the major benefits of reconstruction.

  15. Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae)

    OpenAIRE

    Desmawati Iska; Zandberg Katrina; Reyes Michelle; de Bellard Maria E

    2010-01-01

    Abstract Background The neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their ...

  16. Mast cell progenitors: origin, development and migration to tissues.

    Science.gov (United States)

    Dahlin, Joakim S; Hallgren, Jenny

    2015-01-01

    Mast cells in tissues are developed from mast cell progenitors emerging from the bone marrow in a process highly regulated by transcription factors. Through the advancement of the multicolor flow cytometry technique, the mast cell progenitor population in the mouse has been characterized in terms of surface markers. However, only cell populations with enriched mast cell capability have been described in human. In naïve mice, the peripheral tissues have a constitutive pool of mast cell progenitors. Upon infections in the gut and in allergic inflammation in the lung, the local mast cell progenitor numbers increase tremendously. This review focuses on the origin and development of mast cell progenitors. Furthermore, the evidences for cells and molecules that govern the migration of these cells in mice in vivo are described.

  17. Effect of human neural progenitor cells on injured spinal cord

    Institute of Scientific and Technical Information of China (English)

    XU Guang-hui; BAI Jin-zhu; CAI Qin-lin; LI Xiao-xia; LI Ling-song; SHEN Li

    2005-01-01

    Objective: To study whether human neural progenitor cells can differentiate into neural cells in vivo and improve the recovery of injured spinal cord in rats.Methods: Human neural progenitor cells were transplanted into the injured spinal cord and the functional recovery of the rats with spinal cord contusion injury was evaluated with Basso-Beattie-Bresnahan (BBB) locomotor scale and motor evoked potentials. Additionally, the differentiation of human neural progenitor cells was shown by immunocytochemistry.Results: Human neural progenitor cells developed into functional cells in the injured spinal cord and improved the recovery of injured spinal cord in both locomotor scores and electrophysiological parameters in rats.Conclusions: Human neural progenitor cells can treat injured spinal cord, which may provide a new cell source for research of clinical application.

  18. GSK-3 is a master regulator of neural progenitor homeostasis

    Science.gov (United States)

    Kim, Woo-Yang; Wang, Xinshuo; Wu, Yaohong; Doble, Bradley W; Patel, Satish; Woodgett, James R; Snider, William D

    2016-01-01

    The development of the brain requires the exquisite coordination of progenitor proliferation and differentiation to achieve complex circuit assembly. It has been suggested that glycogen synthase kinase 3 (GSK-3) acts as an integrating molecule for multiple proliferation and differentiation signals because of its essential role in the RTK, Wnt and Shh signaling pathways. We created conditional mutations that deleted both the α and β forms of GSK-3 in mouse neural progenitors. GSK-3 deletion resulted in massive hyperproliferation of neural progenitors along the entire neuraxis. Generation of both intermediate neural progenitors and postmitotic neurons was markedly suppressed. These effects were associated with the dysregulation of β-catenin, Sonic Hedgehog, Notch and fibroblast growth factor signaling. Our results indicate that GSK-3 signaling is an essential mediator of homeostatic controls that regulate neural progenitors during mammalian brain development. PMID:19801986

  19. Hepatic progenitor cells in human liver tumor development

    Institute of Scientific and Technical Information of China (English)

    Louis Libbrecht

    2006-01-01

    In recent years, the results of several studies suggest that human liver tumors can be derived from hepatic progenitor cells rather than from mature cell types.The available data indeed strongly suggest that most combined hepatocellular-cholangiocarcinomas arise from hepatic progenitor cells that retained their potential to differentiate into the hepatocytic and biliary lineages.Hepatic progenitor cells could also be the basis for some hepatocellular carcinomas and hepatocellular adenomas, although it is very difficult to determine the origin of an individual hepatocellular carcinoma. There is currently not enough data to make statements regarding a hepatic progenitor cell origin of cholangiocarcinoma.The presence of hepatic progenitor cell markers and the presence and extent of the cholangiocellular component are factors that are related to the prognosis of hepatocellular carcinomas and combined hepatocellularcholangiocarcinomas, respectively.

  20. Differential requirements of BMP and Wnt signalling during gastrulation and neurulation define two steps in neural crest induction.

    Science.gov (United States)

    Steventon, Ben; Araya, Claudio; Linker, Claudia; Kuriyama, Sei; Mayor, Roberto

    2009-03-01

    The neural crest is induced by a combination of secreted signals. Although previous models of neural crest induction have proposed a step-wise activation of these signals, the actual spatial and temporal requirement has not been analysed. Through analysing the role of the mesoderm we show for the first time that specification of neural crest requires two temporally and chemically different steps: first, an induction at the gastrula stage dependent on signals arising from the dorsolateral mesoderm; and second, a maintenance step at the neurula stage dependent on signals from tissues adjacent to the neural crest. By performing tissue recombination experiments and using specific inhibitors of different inductive signals, we show that the first inductive step requires Wnt activation and BMP inhibition, whereas the later maintenance step requires activation of both pathways. This change in BMP necessity from BMP inhibition at gastrula to BMP activation at neurula stages is further supported by the dynamic expression of BMP4 and its antagonists, and is confirmed by direct measurements of BMP activity in the neural crest cells. The differential requirements of BMP activity allow us to propose an explanation for apparently discrepant results between chick and frog experiments. The demonstration that Wnt signals are required for neural crest induction by mesoderm solves an additional long-standing controversy. Finally, our results emphasise the importance of considering the order of exposure to signals during an inductive event.

  1. Quantitative and qualitative morphologic, cytochemical and ultrastructural characteristics of blood cells in the Crested Serpent eagle and Shikra.

    Science.gov (United States)

    Salakij, Chaleow; Kasorndorkbua, Chaiyan; Salakij, Jarernsak; Suwannasaeng, Pimsuda; Jakthong, Pattarapong

    2015-08-01

    The Crested Serpent eagle (Spilornis cheela) is a bird of prey found in the tropical rain forest in Thailand. The Shikra (Accipiter badius) is a sparrow hawk and common resident in Thailand. Blood samples from 9 Crested Serpent eagles and 12 Shikras were obtained from September 2010 to November 2014. They were clinically healthy and negative for blood parasites detectable by light microscopy and molecular techniques (partial cytochrome b gene for avian malaria and partial 18S rRNA gene for trypanosome). Cytochemical staining (Sudan black B, peroxidase, α-naphthyl acetate esterase, and β-glucuronidase) and transmission electron microscopy were performed. Hematological results were reported as the mean ± standard deviation and median. Heterophils were the most prevalent leukocytes in the Crested Serpent eagle, but in the Shikra, lymphocytes were the most prevalent leukocytes. In the Shikra, some vacuoles were observed in the cytoplasm of the eosinophils. All blood cells in both types of raptors stained positively for β-glucuronidase but negatively for peroxidase. The ultrastructure of heterophils showed more clearly differentiate long rod granules in Crested Serpent eagle and spindle-shaped granules in Shikra. The ultrastructure of the eosinophils in the Crested Serpent eagle revealed varied electron-dense, round-shaped granules with round, different electron-dense areas in the centers of some granules, which differed from the structure reported for other raptors. These quantitative results may be useful for clinical evaluations of Crested Serpent eagles and Shikras that are undergoing rehabilitation for release.

  2. Neural Crest Cells Isolated from the Bone Marrow of Transgenic Mice Express JCV T-Antigen.

    Directory of Open Access Journals (Sweden)

    Jennifer Gordon

    Full Text Available JC virus (JCV, a common human polyomavirus, is the etiological agent of the demyelinating disease, progressive multifocal leukoencephalopathy (PML. In addition to its role in PML, studies have demonstrated the transforming ability of the JCV early protein, T-antigen, and its association with some human cancers. JCV infection occurs in childhood and latent virus is thought to be maintained within the bone marrow, which harbors cells of hematopoietic and non-hematopoietic lineages. Here we show that non-hematopoietic mesenchymal stem cells (MSCs isolated from the bone marrow of JCV T-antigen transgenic mice give rise to JCV T-antigen positive cells when cultured under neural conditions. JCV T-antigen positive cells exhibited neural crest characteristics and demonstrated p75, SOX-10 and nestin positivity. When cultured in conditions typical for mesenchymal cells, a population of T-antigen negative cells, which did not express neural crest markers arose from the MSCs. JCV T-antigen positive cells could be cultured long-term while maintaining their neural crest characteristics. When these cells were induced to differentiate into neural crest derivatives, JCV T-antigen was downregulated in cells differentiating into bone and maintained in glial cells expressing GFAP and S100. We conclude that JCV T-antigen can be stably expressed within a fraction of bone marrow cells differentiating along the neural crest/glial lineage when cultured in vitro. These findings identify a cell population within the bone marrow permissible for JCV early gene expression suggesting the possibility that these cells could support persistent viral infection and thus provide clues toward understanding the role of the bone marrow in JCV latency and reactivation. Further, our data provides an excellent experimental model system for studying the cell-type specificity of JCV T-antigen expression, the role of bone marrow-derived stem cells in the pathogenesis of JCV-related diseases

  3. Yes-associated protein 65 (YAP expands neural progenitors and regulates Pax3 expression in the neural plate border zone.

    Directory of Open Access Journals (Sweden)

    Stephen T Gee

    Full Text Available Yes-associated protein 65 (YAP contains multiple protein-protein interaction domains and functions as both a transcriptional co-activator and as a scaffolding protein. Mouse embryos lacking YAP did not survive past embryonic day 8.5 and showed signs of defective yolk sac vasculogenesis, chorioallantoic fusion, and anterior-posterior (A-P axis elongation. Given that the YAP knockout mouse defects might be due in part to nutritional deficiencies, we sought to better characterize a role for YAP during early development using embryos that develop externally. YAP morpholino (MO-mediated loss-of-function in both frog and fish resulted in incomplete epiboly at gastrulation and impaired axis formation, similar to the mouse phenotype. In frog, germ layer specific genes were expressed, but they were temporally delayed. YAP MO-mediated partial knockdown in frog allowed a shortened axis to form. YAP gain-of-function in Xenopus expanded the progenitor populations in the neural plate (sox2(+ and neural plate border zone (pax3(+, while inhibiting the expression of later markers of tissues derived from the neural plate border zone (neural crest, pre-placodal ectoderm, hatching gland, as well as epidermis and somitic muscle. YAP directly regulates pax3 expression via association with TEAD1 (N-TEF at a highly conserved, previously undescribed, TEAD-binding site within the 5' regulatory region of pax3. Structure/function analyses revealed that the PDZ-binding motif of YAP contributes to the inhibition of epidermal and somitic muscle differentiation, but a complete, intact YAP protein is required for expansion of the neural plate and neural plate border zone progenitor pools. These results provide a thorough analysis of YAP mediated gene expression changes in loss- and gain-of-function experiments. Furthermore, this is the first report to use YAP structure-function analyzes to determine which portion of YAP is involved in specific gene expression changes and the

  4. A comparative evaluation of the in vitro penetration performance of the improved Crest complete toothbrush versus the Current Crest complete toothbrush, the Colgate Precision toothbrush and the Oral-B P40 toothbrush.

    Science.gov (United States)

    Volpenhein, D W; Handel, S E; Hughes, T J; Wild, J

    1996-01-01

    Removal of plaque and debris from interproximal surfaces during toothbrushing has generally been difficult to achieve, in large part because traditional flat-bristled toothbrushes do not offer good interproximal penetration. As a result, a number of varying bristle designs have been developed, with the rippled-design brush shown to be particularly effective at removing interproximal plaque. Recently, an existing brush, the original Crest Complete, was modified to offer a more deeply rippled version. This study evaluated the interproximal penetration of four bristle designs: rippled pattern (original Crest Complete), deeper rippled pattern (improved Crest Complete), multi-level (Colgate Precision), and flat-tufted (Oral-B P40). The study used a previously reported in vitro model for determining interproximal penetration of manual toothbrushes (J Clin Dent 5:27-33, 1994). In order to effectively mimic the in-use characteristics of toothbrushing, this model is based on analysis of videotaped consumer brushing habits, tooth morphology, and in vivo plaque tenacity characteristics and uses the three most predominantly used brushing techniques (circular, up-and-down, and back-and-forth, with the brush held at both 45 and 90 degrees to the tooth surface). In addition, the model's brush stroke length, brush force, and brush speed are likewise based on analysis of consumer brushing patterns. The results of the study indicate that the new Crest Complete with deeper rippled bristles provided significantly superior (p Colgate Precision and Oral-B brushes overall and for three of the four brush strokes tested. In addition, the new Crest Complete was found to provide significantly superior interproximal penetration to the original Crest Complete overall and in circular and up-and-down strokes, and the original Crest Complete provided superior overall interproximal penetration to the Colgate and Oral-B brushes.

  5. Cardiac Progenitor Cell Extraction from Human Auricles

    KAUST Repository

    Di Nardo, Paolo

    2017-02-22

    For many years, myocardial tissue has been considered terminally differentiated and, thus, incapable of regenerating. Recent studies have shown, instead, that cardiomyocytes, at least in part, are slowly substituted by new cells originating by precursor cells mostly embedded into the heart apex and in the atria. We have shown that an elective region of progenitor cell embedding is represented by the auricles, non-contractile atria appendages that can be easily sampled without harming the patient. The protocol here reported describes how from auricles a population of multipotent, cardiogenic cells can be isolated, cultured, and differentiated. Further studies are needed to fully exploit this cell population, but, sampling auricles, it could be possible to treat cardiac patients using their own cells circumventing rejection or organ shortage limitations.

  6. PET imaging of adoptive progenitor cell therapies.

    Energy Technology Data Exchange (ETDEWEB)

    Gelovani, Juri G.

    2008-05-13

    Objectives. The overall objective of this application is to develop novel technologies for non-invasive imaging of adoptive stem cell-based therapies with positron emission tomography (PET) that would be applicable to human patients. To achieve this objective, stem cells will be genetically labeled with a PET-reporter gene and repetitively imaged to assess their distribution, migration, differentiation, and persistence using a radiolabeled reporter probe. This new imaging technology will be tested in adoptive progenitor cell-based therapy models in animals, including: delivery pro-apoptotic genes to tumors, and T-cell reconstitution for immunostimulatory therapy during allogeneic bone marrow progenitor cell transplantation. Technical and Scientific Merits. Non-invasive whole body imaging would significantly aid in the development and clinical implementation of various adoptive progenitor cell-based therapies by providing the means for non-invasive monitoring of the fate of injected progenitor cells over a long period of observation. The proposed imaging approaches could help to address several questions related to stem cell migration and homing, their long-term viability, and their subsequent differentiation. The ability to image these processes non-invasively in 3D and repetitively over a long period of time is very important and will help the development and clinical application of various strategies to control and direct stem cell migration and differentiation. Approach to accomplish the work. Stem cells will be genetically with a reporter gene which will allow for repetitive non-invasive “tracking” of the migration and localization of genetically labeled stem cells and their progeny. This is a radically new approach that is being developed for future human applications and should allow for a long term (many years) repetitive imaging of the fate of tissues that develop from the transplanted stem cells. Why the approach is appropriate. The novel approach to

  7. New approaches to SNe Ia progenitors

    CERN Document Server

    Ruiz-Lapuente, Pilar

    2014-01-01

    Although Type Ia supernovae (SNe Ia) are a major tool in cosmology and play a key role in the chemical evolution of galaxies, the nature of their progenitor systems (apart from the fact that they must be close binaries containing at least one white dwarf) remains largely unknown. In the last decade, considerable efforts have been made, both observationally and theoretically, to solve this problem. Observations have, however, revealed a previously unsuspected variety of events, ranging from very underluminous outbursts to clearly overluminous ones, and spanning a range well outside the peak luminosity--decline rate of the light curve relationship, used to make calibrated candles of the SNe Ia. On the theoretical side, new explosion scenarios, such as violent mergings of pairs of white dwarfs, have been explored. We review those recent developments, emphasizing the new observational findings, but also trying to tie them to the different scenarios and explosion mechanisms proposed thus far.

  8. Lack of organ specific commitment of vagal neural crest cell derivatives as shown by back-transplantation of GFP chicken tissues.

    Science.gov (United States)

    Freem, Lucy J; Delalande, Jean Marie; Campbell, Alison M; Thapar, Nikhil; Burns, Alan J

    2012-01-01

    Neural crest cells (NCC) are multipotent progenitors that migrate extensively throughout the developing embryo and generate a diverse range of cell types. Vagal NCC migrate from the hindbrain into the foregut and from there along the gastrointestinal tract to form the enteric nervous system (ENS), the intrinsic innervation of the gut, and into the developing lung buds to form the intrinsic innervation of the lungs. The aim of this study was to determine the developmental potential of vagal NCC that had already colonised the gut or the lungs. We used transgenic chicken embryos that ubiquitously express green fluorescent protein (GFP) to permanently mark and fate-map vagal NCC using intraspecies grafting. This was combined with back-transplantation of gut and lung segments, containing GFP-positive NCC, into the vagal region of a second recipient embryo to determine, using immunohistochemical staining, whether gut or lung NCC are competent of re-colonising both these organs, or whether their fate is restricted. Chick(GFP)-chick intraspecies grafting efficiently labelled NCC within the gut and lung of chick embryos. When segments of embryonic day (E)5.5 pre-umbilical midgut containing GFP-positive NCC were back-transplanted into the vagal region of E1.5 host embryos, the GFP-positive NCC remigrated to colonise both the gut and lungs and differentiated into neurons in stereotypical locations. However, GFP-positive lung NCC did not remigrate when back-transplanted. Our studies suggest that gut NCC are not restricted to colonising only this organ, since upon back-transplantation GFP-positive gut NCC colonised both the gut and the lung.

  9. Thrombopoietin is a growth factor for rat hepatic progenitors.

    Science.gov (United States)

    Schmelzer, Eva; Deiwick, Andrea; Bruns, Helge; Fiegel, Henning C; Bader, Augustinus

    2008-03-01

    The liver is the primary site of hematopoiesis during fetal development; it has been shown that thrombopoietin (TPO) produced by the liver during fetal development is a major regulator of megakaryocytopoiesis. As maximum liver growth and hematopoiesis occur simultaneously, we hypothesized that TPO may act as a growth factor for hepatic progenitors. Therefore, the influence of TPO on the proliferation of fetal hepatic progenitors in vitro compared with that of adult hepatocytes was analyzed. The expression of the TPO receptor, c-mpl, was investigated in fetal and adult liver. Cell proliferation was measured by bromodeoxyuridine incorporation and total cell counts. TPO and c-mpl gene expression was investigated by reverse transcription polymerase chain reaction. The cell surface expression of c-mpl was analyzed in fetal and adult human liver by immunohistochemistry. Hepatic progenitors of fetal and adult liver but not hepatocytes expressed the TPO receptor, c-mpl, on the cell surface. Fetal hepatic progenitors expressed mRNA for TPO and its receptor. TPO stimulated cell proliferation and increased cell numbers of cultured rat fetal hepatic progenitors but not adult hepatocytes. We conclude that TPO acts in addition to its known role in megakaryocytopoiesis as a growth factor for hepatic progenitors but not hepatocytes in vitro; thus, TPO represents a growth factor for hepatic progenitors during fetal liver development.

  10. Fate mapping in embryos of Neoceratodus forsteri reveals cranial neural crest participation in tooth development is conserved from lungfish to tetrapods.

    Science.gov (United States)

    Kundrát, Martin; Joss, Jean M P; Smith, Moya M

    2008-01-01

    Experimental evidence that the neural crest participates in tooth development in any osteichthyan fish has so far been lacking. Using vital dye cell-lineage tracking, we demonstrate that trigeminal stream neural crest cells contribute to the dental papilla of developing teeth in the Australian lungfish. Trigeminal neural crest cells labeled before migration have been traced during the earliest stages of tooth development. Neural crest cells from a single midbrain locus were relocated as ectomesenchyme in all developing teeth of the lungfish regardless of their topographical position in the dentition. These cells remain at the dental papilla interface and become cells committed to dentine production. Our findings provide the first cell-lineage evidence that cranial neural crest is fated to ectomesenchyme for tooth development and dentine production in the living sister-group to tetrapods. This shows that cranial neural crest contribution to teeth is conserved from this node on the tetrapod phylogeny.

  11. Vascular smooth muscle progenitor cells: building and repairing blood vessels.

    Science.gov (United States)

    Majesky, Mark W; Dong, Xiu Rong; Regan, Jenna N; Hoglund, Virginia J

    2011-02-04

    Molecular pathways that control the specification, migration, and number of available smooth muscle progenitor cells play key roles in determining blood vessel size and structure, capacity for tissue repair, and progression of age-related disorders. Defects in these pathways produce malformations of developing blood vessels, depletion of smooth muscle progenitor cell pools for vessel wall maintenance and repair, and aberrant activation of alternative differentiation pathways in vascular disease. A better understanding of the molecular mechanisms that uniquely specify and maintain vascular smooth muscle cell precursors is essential if we are to use advances in stem and progenitor cell biology and somatic cell reprogramming for applications directed to the vessel wall.

  12. Progenitor cell therapy for sacral pressure sore: a pilot study with a novel human chronic wound model.

    Science.gov (United States)

    Wettstein, Reto; Savic, Miodrag; Pierer, Gerhard; Scheufler, Oliver; Haug, Martin; Halter, Jörg; Gratwohl, Alois; Baumberger, Michael; Schaefer, Dirk Johannes; Kalbermatten, Daniel Felix

    2014-01-29

    Chronic wounds are a major health-care issue, but research is limited by the complexity and heterogeneity in terms of wound etiology as well as patient-related factors. A suitable animal model that replicates the situation in humans is not available. Therefore, the aim of the present work is to present a standardized human wound model and the data of a pilot study of topically applied progenitor cells in a sacral pressure sore. Three patients underwent cell harvest from the iliac crest at the time of the initial debridement. Forty-eight hours after bone marrow harvest and debridement, the CD34+ selected cell suspension was injected into the wound. With the aid of a laser scanner, three-dimensional analyses of wound morphometry were performed until the defect was reconstructed with a local flap 3 weeks after debridement. Decreases in volume to 60%±6% of baseline on the sham side and to 52%±3% of baseline on the cell side were measured. Histologic work-up revealed no signs of metaplastic, dysplastic, or neoplastic proliferation/differentiation after progenitor cell treatment. CD34+ cells were detected in the biopsies of day 0. The pressure sore wound model allows investigation of the initial 3 weeks after cell-based therapy. Objective outcome analysis in terms of wound volume and histology can be performed without, or with, minimal additional morbidity, and the anatomy of the sacral area allows a control and study side in the same patient. Therefore, this model can serve as a standard for wound-healing studies. ClinicalTrials.gov NCT00535548.

  13. Lineage tracing of neuromesodermal progenitors reveals novel Wnt-dependent roles in trunk progenitor cell maintenance and differentiation.

    Science.gov (United States)

    Garriock, Robert J; Chalamalasetty, Ravindra B; Kennedy, Mark W; Canizales, Lauren C; Lewandoski, Mark; Yamaguchi, Terry P

    2015-05-01

    In the development of the vertebrate body plan, Wnt3a is thought to promote the formation of paraxial mesodermal progenitors (PMPs) of the trunk region while suppressing neural specification. Recent lineage-tracing experiments have demonstrated that these trunk neural progenitors and PMPs derive from a common multipotent progenitor called the neuromesodermal progenitor (NMP). NMPs are known to reside in the anterior primitive streak (PS) region; however, the extent to which NMPs populate the PS and contribute to the vertebrate body plan, and the precise role that Wnt3a plays in regulating NMP self-renewal and differentiation are unclear. To address this, we used cell-specific markers (Sox2 and T) and tamoxifen-induced Cre recombinase-based lineage tracing to locate putative NMPs in vivo. We provide functional evidence for NMP location primarily in the epithelial PS, and to a lesser degree in the ingressed PS. Lineage-tracing studies in Wnt3a/β-catenin signaling pathway mutants provide genetic evidence that trunk progenitors normally fated to enter the mesodermal germ layer can be redirected towards the neural lineage. These data, combined with previous PS lineage-tracing studies, support a model that epithelial anterior PS cells are Sox2(+)T(+) multipotent NMPs and form the bulk of neural progenitors and PMPs of the posterior trunk region. Finally, we find that Wnt3a/β-catenin signaling directs trunk progenitors towards PMP fates; however, our data also suggest that Wnt3a positively supports a progenitor state for both mesodermal and neural progenitors. © 2015. Published by The Company of Biologists Ltd.

  14. Backfill for iliac-crest donor sites: a prospective, randomized study of coralline hydroxyapatite.

    Science.gov (United States)

    Bojescul, John A; Polly, David W; Kuklo, Timothy R; Allen, Thomas W; Wieand, Kay E

    2005-08-01

    We report on a prospective randomized study of coralline hydroxyapatite (CH) used as backfill for iliac-crest donor sites. Autogenous iliac-crest bone graft is routinely harvested for spinal fusion. Donor-site morbidity is underappreciated; the presumption is that donor sites regenerate. In this study, we assessed the biological viability of the backfill CH (Pro OsteonTM Implant 500 Hydroxyapatite Bone Void Filler; Interpore, Irvine, Calif) and compared donor-site morbidity after harvest. Twelve patients (11 men, 1 woman) were enrolled: 5 in the backfill group and 7 in the no-backfill group. As part of routine evaluations done preoperatively and 6 weeks, 3 months, 6 months, and 1 year postoperatively, plain radiographs and computed tomography (CT) scans were used to assess bone ingrowth, and technetium bone scans were used to assess biological activity. Postoperative pain analysis was also done. Ten patients (9 men, 1 woman) completed the study. Of the 4 completers in the backfill group, 3 (75%) showed bony ingrowth on plain radiographs and CT scans at 1 year; the fourth patient showed bony ingrowth only on plain radiographs. All 4 patients showed biological activity on bone scans and reported mild pain to no pain. Of the 6 completers in the no-backfill group, 1 (17%) showed bony ingrowth on plain radiographs and CT scans. No patient showed biological activity on bone scans at 1 year. CH aids in iliac-crest healing after bone-graft harvesting by acting as a biological osteoconductive matrix. Postoperative pain at the bone-graft site is potentially reduced. More studies of larger numbers of patients are needed to assess the true long-term benefits of this material in a clinical setting.

  15. Population structure and mating system of the Red-crested Korhaan (Lophotis ruficrista) in South Africa

    Institute of Scientific and Technical Information of China (English)

    Johann H van Niekerk

    2015-01-01

    Background:The mating system of the korhaans and bustards in southern Africa is either based on polygyny or monogamy. The Red-crested Korhaan (Lophotis ruficrista) has been described as polygynous but otherwise very little is known about its breeding biology. The aims were to describe the population structure and male behavior during breeding. Methods:The data collected for this paper was mainly based on field transect surveys carried out in 2009, 2010 and 2011. The population structure of the Red-crested Korhaan in the temperate Borakalalo Game Reserve (BGR) was compared with that in the arid Molopo Nature Reserve (MNR) (both situated in the North West province of South Africa). The study was mainly conducted in the BGR but additional work was conducted in the MNR for comparison. Results:The difference in mean group sizes between MNR (1.03) and BGR (1.07) was statistically not significant. Group sizes were not affected by climate despite the fact that the BGR received about 650 mm precipitation per annum and the MNR about 200 mm. In both reserves the apparent sex ratios were skewed in favor of males (1:0.29 in the BGR and 1:0.1 in the MNR). The population was dispersed in a clumped manner which is ascribed to the formation of leks. Leks were positioned in open habitat while females invariably concealed themselves under cover. Conclusions:The leks formed the pivot of the mating system of the Red-crested Korhaan and are identifiable social structures that field ecologists can use to monitor population stability.

  16. Iliac crest allograft glenoid reconstruction for recurrent anterior shoulder instability in athletes: Surgical technique and results

    Directory of Open Access Journals (Sweden)

    Randy Mascarenhas

    2014-01-01

    Full Text Available Performing a labral repair alone in patients with recurrent anterior instability and a large glenoid defect has led to poor outcomes. We present a technique involving the use of the iliac crest allograft inserted into the glenoid defect in athletes with recurrent anterior shoulder instability and large bony defects of the glenoid (>25% of glenoid diameter. All athletes with recurrent anterior shoulder instability and a large glenoid defect that underwent open anterior shoulder stabilization and glenoid reconstruction with the iliac crest allograft were followed over a 4-year period. Preoperatively, a detailed history and physical exam were obtained along with standard radiographs and magnetic resonance imaging of the affected shoulder. All patients also completed the Simple Shoulder Test (SST and American Shoulder and Elbow Surgeons (ASES evaluation forms preoperatively. A computed tomography scan was obtained postoperatively to assess osseous union of the graft and the patient again went through a physical exam in addition to completing the SST, ASES, and Western Ontario Shoulder Instability Index (WOSI forms. 10 patients (9 males, 1 female were followed for an average of 16 months (4-36 months and had a mean age of 24.4 years. All patients exhibited a negative apprehension/relocation test and full shoulder strength at final follow-up. Eight of 10 patients had achieved osseous union at 6 months (80.0%. ASES scores improved from 64.3 to 97.8, and SST scores improved from 66.7 to 100. Average postoperative WOSI scores were 93.8%. The use of the iliac crest allograft provides a safe and clinically useful alternative compared to previously described procedures for recurrent shoulder instability in the face of glenoid deficiency.

  17. Comparison of NOAA-CREST Soil Moisture Measurements with SMOS Products

    Science.gov (United States)

    Norouzi, H.; Forbes, A.

    2014-12-01

    In October 2014, the Soil Moisture Active and Passive mission (SMAP) will launch into a near-polar and sun- synchronous orbit. SMAP includes the first 3 KM resolution product, by both radar and radiometer sensors which will transmit useful information concentrating on the global measurements of soil moisture and freeze/thaw cycles. NOAA- CREST (National Oceanic and Atmospheric Administration- Cooperative Remote Sensing Science and Technology) deploys a series of in-situ devices into the soil, and an L-BAND Radiometer close to the site ground at the Cary Institute in Millbrook, NY. The site is important for future validation of SMAP mission. Comparing mathematical and ground based remote sensing of soil moisture is beneficial to ensure the accuracy of the measurements. The focus of this research is to analyze and compare soil moisture from ESA- SMOS (Europe Space Agency- Soil Moisture Ocean Salinity) mission and the Cary Institute's soil moisture measurements within the same time period, and location. In the interest of establishing superb authentication; comparing SMOS and ground measurements will justify the accuracy of the newly launch satellite. Discrepancies can be found between field point measurement and relatively large footprint of SMOS, which affects comparison and validation. Several techniques and statistical methods will provide a more meaningful comparison to analyze soil moisture data. The results of this project will help to provide a useful method to compare the NOAA-CREST soil moisture measurements and SMAP measurements. In conclusion, the SMAP advance technology will provide more accurate feedback for modeling numerical weather and climate models. Keywords: Soil Moisture, Precipitation, CREST-SMART, Cary Institute, In-situ, Remote Sensors Accurate Soil Moisture Data, Millbrook, N.Y., CATDS, Hydrology is the branch of science concerning properties of earth's water especially its movement in relation to land. SMOS MIRAS, SMAP, Sensors (Underground)

  18. Resurrection of Bronchocela burmana Blanford, 1878 for the Green Crested Lizard (Squamata, Agamidae of southern Myanmar

    Directory of Open Access Journals (Sweden)

    George R. Zug

    2017-02-01

    Full Text Available Recent fieldwork in southern Tanintharyi revealed the presence of a small Green Crested Lizard in the wet evergreen forest. We generated mtDNA sequence data (ND2 that demonstrates that this population’s nearest relative is Bronchocela rayaensis Grismer et al., 2015 of Pulau Langkawi, northwestern Peninsular Malaysia and Phuket Island. Morphologically the Burmese Bronchocela shares many features with B. rayaensis, which potentially would make this recently described Thai-Malay species a synonym of Bronchocela burmana Blanford, 1878; however, we interpret the genetic and morphological differences to reflect evolutionary divergence and recommend the recognition of both species.

  19. Numerical simulation of lowest-order short-crested wave instabilities

    DEFF Research Database (Denmark)

    Fuhrman, David R.; Madsen, Per A.; Bingham, Harry

    2006-01-01

    instabilities. These correctly lead to well-known (nearly symmetric) recurrence cycles below a previously established breaking threshold steepness, and to an asymmetric evolution (characterized by a permanent transfer of energy to the lower side-band) above this threshold, with dissipation from a smoothing......-bands. At larger steepness, the evolution leads to a permanent downshift of both the mean and peak frequencies, driven in part by dissipation, effectively breaking the quasi-recurrence cycle. A single case involving a class Ib short-crested wave instability at relatively large steepness is also considered, which...

  20. The Crest of the Peacock Non-European Roots of Mathematics (Third Edition)

    CERN Document Server

    Joseph, George Gheverghese

    2011-01-01

    From the Ishango Bone of central Africa and the Inca quipu of South America to the dawn of modern mathematics, The Crest of the Peacock makes it clear that human beings everywhere have been capable of advanced and innovative mathematical thinking. George Gheverghese Joseph takes us on a breathtaking multicultural tour of the roots and shoots of non-European mathematics. He shows us the deep influence that the Egyptians and Babylonians had on the Greeks, the Arabs' major creative contributions, and the astounding range of successes of the great civilizations of India and China. The third editio