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Sample records for achieve sustained erythroid

  1. Using Design To Achieve Sustainability

    EPA Science Inventory

    Sustainability is defined as meeting the needs of this generation without compromising the ability of future generations to meet their needs. This is a conditional statement that places the responsibility for achieving sustainability squarely in hands of designers and planners....

  2. Achieving sustainable cultivation of potatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Every phase of the production cycle impacts the sustainability of potato. Potato physiology determines how genetically encoded developmental attributes interact with local environmental conditions as modified through agricultural practice to produce a perishable crop. In this chapter we highlight ho...

  3. Achieving a sustainable service advantage.

    PubMed

    Coyne, K P

    1993-01-01

    Many managers believe that superior service should play little or no role in competitive strategy; they maintain that service innovations are inherently copiable. However, the author states that this view is too narrow. For a company to achieve a lasting service advantage, it must base a new service on a capability gap that competitors cannot or will not copy. PMID:10123422

  4. Factors Contributing to Institutions Achieving Environmental Sustainability

    ERIC Educational Resources Information Center

    James, Matthew; Card, Karen

    2012-01-01

    Purpose: The purpose of this paper is to determine what factors contributed to three universities achieving environmental sustainability. Design/methodology/approach: A case study methodology was used to determine how each factor contributed to the institutions' sustainability. Site visits, fieldwork, document reviews, and interviews with…

  5. ACHIEVING SUSTAINABILITY - FINAL STEPS IN A DYNAMIC DANCE

    EPA Science Inventory

    Achieving sustainability relies upon adequate metrics to evaluate the environment and guide decisions. Although adequate assessment is important to prescribing remedies, achieving a sustainable environment cannot be delayed. It must be achieved today as well as tomorrow so that t...

  6. Achieving true sustainability of zoo populations.

    PubMed

    Lacy, Robert C

    2013-01-01

    For the last 30 years, cooperative management of irreplaceable animal populations in zoos and aquariums has focused primarily on the goal of minimizing genetic decay within defined time frames, and large advances have been made in technologies to optimize genetic management of closed populations. However, recent analyses have shown that most zoo programs are not projected to meet their stated goals. This has been described as a lack of achieving "sustainability" of the populations, yet by definition a goal of managed decay is not a plan for sustainability. True sustainability requires management of the resource in manner that does not deplete its value for the future. Achieving such sustainability for many managed populations may require changing from managing isolated populations to managing populations that are part of a broader metapopulation, with carefully considered exchange between populations across a spectrum of ex situ to in situ. Managing zoo populations as components of comprehensive conservation strategies for the species will require research on determinants of various kinds of genetic, physiological, behavioral, and morphological variation and their roles in population viability, development of an array of management techniques and tools, training of population managers in metapopulation management and integrated conservation planning, and projections of impacts of management strategies on the viability of the captive populations and all populations that are interactively managed or affected. Such a shift in goals and methods would result in zoo population management being an ongoing part of species conservation rather than short-term or isolated from species conservation. Zoo Biol. 32:19-26, 2013. © 2012 Wiley Periodicals, Inc. PMID:22753040

  7. Perspectives on achieving sustainable energy production and use

    EPA Science Inventory

    The traditional definition of sustainability calls for polices and strategies that meet society's present needs without compromising the ability of future generations to meet their own needs. Achieving operational sustainability requires three critical elements: advances in scien...

  8. Language Teacher Action Research: Achieving Sustainability

    ERIC Educational Resources Information Center

    Edwards, Emily; Burns, Anne

    2016-01-01

    Action research (AR) is becoming increasingly popular in ELT contexts as a means of continuous professional development. The positive impacts of AR on language teacher development are well documented, but the important question of how those impacts can be sustained over time is virtually unexplored. Drawing on findings from a study of teachers in…

  9. ACHIEVING SUSTAINABILITY THROUGH LIFE CYCLE STRATEGIES

    EPA Science Inventory

    Sustainability is, of course, not a recent concept. But our understanding of what it means and what we need to do to meet the challenge it presents continues to grow. Throughout the ages, nations have had to address the issue of harmony between the environment, society and the e...

  10. Achieving sustainable biomaterials by maximising waste recovery.

    PubMed

    Glew, David; Stringer, Lindsay C; McQueen-Mason, Simon

    2013-06-01

    The waste hierarchy of 'reduce, reuse, recycle, recover' can be followed to improve the sustainability of a product, yet it is not applied in any meaningful way in the biomaterials industry which focuses more on sustainable sourcing of inputs. This paper presents the results of industry interviews and a focus group with experts to understand how waste recovery of biomaterials could become more widespread. Interview findings were used to develop three scenarios: (1) do nothing; (2) develop legislation; and (3) develop certification standards. These scenarios formed the basis for discussions at an expert focus group. Experts considered that action was required, rejecting the first scenario. No preference was apparent for scenarios (2) and (3). Experts agreed that there should be collaboration on collection logistics, promotion of demand through choice editing, product 'purity' could be championed though certification and there should be significant investment and research into recovery technologies. These considerations were incorporated into the development of a model for policy makers and industry to help increase biomaterial waste recovery. PMID:23562447

  11. Sustaining School Achievement in California's Elementary Schools after State Monitoring

    ERIC Educational Resources Information Center

    McCabe, Molly

    2010-01-01

    This study examined the Academic Performance Index (API) and Adequate Yearly Progress (AYP) achievement trends between 2004 and 2006 of 58 California public elementary schools after exiting state monitoring and investigated practices for sustaining consistent achievement growth. Statistical methods were used to analyze statewide achievement trends…

  12. Leadership Effects on Student Achievement and Sustained School Success

    ERIC Educational Resources Information Center

    Jacobson, Stephen

    2011-01-01

    Purpose: The purpose of this paper is to examine the effects of leadership on student achievement and sustained school success, especially in challenging, high-poverty schools. Design/methodology/approach: The paper combines a review of the leadership literature with findings drawn from longitudinal studies of the International Successful School…

  13. Do Intelligence and Sustained Attention Interact in Predicting Academic Achievement?

    ERIC Educational Resources Information Center

    Steinmayr, Ricarda; Ziegler, Mattias; Trauble, Birgit

    2010-01-01

    Research in clinical samples suggests that the relationship between intelligence and academic achievement might be moderated by sustained attention. The present study aimed to explore whether this interaction could be observed in a non-clinical sample. We investigated a sample of 11th and 12th grade students (N = 231). An overall performance score…

  14. DEVELOPMENT AND APPLICATION OF PLANNING PROCESS TO ACHIEVE SUSTAINABILITY

    EPA Science Inventory

    Concepts of sustainability are numerous, widely discussed, and necessary, but sustainability needs to be applied to development projects to succeed. However, few applications are made and their measures are unclear. Sustainability indicators are typically used as measures, but ...

  15. Achieving and Maintaining Existing Building Sustainability Certification at Georgetown University

    ERIC Educational Resources Information Center

    Payant, Richard P.

    2013-01-01

    Sustainability is the promotion of high performance, healthful, energy-efficient, and environmentally stable buildings. Buildings intended for sustainable certification must meet guidelines developed by the Leadership in Energy and Environmental Design (LEED) of the U.S. Green Building Council. The problem is that LEED certification often fails to…

  16. Achieving sustainable plant disease management through evolutionary principles.

    PubMed

    Zhan, Jiasui; Thrall, Peter H; Burdon, Jeremy J

    2014-09-01

    Plants and their pathogens are engaged in continuous evolutionary battles and sustainable disease management requires novel systems to create environments conducive for short-term and long-term disease control. In this opinion article, we argue that knowledge of the fundamental factors that drive host-pathogen coevolution in wild systems can provide new insights into disease development in agriculture. Such evolutionary principles can be used to guide the formulation of sustainable disease management strategies which can minimize disease epidemics while simultaneously reducing pressure on pathogens to evolve increased infectivity and aggressiveness. To ensure agricultural sustainability, disease management programs that reflect the dynamism of pathogen population structure are essential and evolutionary biologists should play an increasing role in their design. PMID:24853471

  17. Sustaining College Students' Persistence and Achievement through Exemplary Instructional Strategies

    ERIC Educational Resources Information Center

    Gentry, Ruben

    2014-01-01

    A "take it or leave it" attitude has no place in higher education. Society needs an educated citizenry to sustain and advance its technological and global mission. Too few students are entering college and even fewer than might reasonably be expected are graduating. Retention and graduation rates serve as key indicators of performance…

  18. Is Sustainability Achievable? Exploring the Limits of Sustainability with Model Systems

    EPA Science Inventory

    Successful implementation of sustainability ideas in ecosystem management requires a basic understanding of the often nonlinear and non-intuitive relationships amongst different dimensions of sustainability, particularly the systemwide implications of human actions. This basic un...

  19. Background, Schooling, and Achievement. Sustaining Effects Study Technical Report 20.

    ERIC Educational Resources Information Center

    Won, Eugene Y. T.; And Others

    This report of a study on the influence of education on student achievement finds that while schooling does have some tangible effects, they are not enough to significantly counterbalance the effects of students' social backgrounds. The report is part of an extensive series of studies on compensatory education and its long-term effects. The study…

  20. Achieving high sustained performance in an unstructured mesh CFD application

    SciTech Connect

    Keyes, D E; Anderson, W K; Gropp, W D; Kaushik, D K; Smith, B F

    1999-12-10

    This paper highlights a three-year project by an interdisciplinary team on a legacy F77 computational fluid dynamics code, with the aim of demonstrating that implicit unstructured grid simulations can execute at rates not far from those of explicit structured grid codes, provided attention is paid to data motion complexity and the reuse of data positioned at the levels of the memory hierarchy closest to the processor, in addition to traditional operation count complexity. The demonstration code is from NASA and the enabling parallel hardware and (freely available) software toolkit are from DOE, but the resulting methodology should be broadly applicable, and the hardware limitations exposed should allow programmers and vendors of parallel platforms to focus with greater encouragement on sparse codes with indirect addressing. This snapshot of ongoing work shows a performance of 15 microseconds per degree of freedom to steady-state convergence of Euler flow on a mesh with 2.8 million vertices using 3072 dual-processor nodes of ASCI Red, corresponding to a sustained floating-point rate of 0.227 Tflop/s.

  1. The Failure of Non-Binding Declarations to Achieve University Sustainability: A Need for Accountability

    ERIC Educational Resources Information Center

    Bekessy, S. A.; Samson, K.; Clarkson, R. E.

    2007-01-01

    Purpose: This paper aims to assess the impact and value of non-binding agreements or declarations in achieving sustainability in universities. Design/methodology/approach: A case study of Royal Melbourne Institute of Technology (RMIT) University is presented, analysing the reasons for lack of progress towards sustainability and evaluating best…

  2. A TWO CENTURY HISTORY OF PACIFIC NORTHWEST SALMON: LESSONS LEARNED FOR ACHIEVING A SUSTAINABLE FUTURE

    EPA Science Inventory

    Achieving ecological sustainability is a daunting challenge. In the Pacific Northwest one of the most highly visible public policy debates concerns the future of salmon populations. Throughout the Pacific Northwest, many wild salmon stocks have declined and some have disappeare...

  3. The Effects of Sustained Silent Reading on Reading Achievement and Reading Attitudes of Fourth Grade Students

    ERIC Educational Resources Information Center

    Gray, Holly Lynn

    2012-01-01

    This study tested the effects of a Sustained Silent Reading program on reading achievement and reading attitude. The study accessed scores from the DIBELS Oral Reading Fluency (Good, Kaminski, & Dill, 2007) to measure reading achievement. This measure was given before and after a twelve week period, during which the treatment group…

  4. Challenges to achievement of metal sustainability in our high-tech society

    SciTech Connect

    Izatt, Reed M.; Izatt, Steven R.; Bruening, Ronald L.; Izatt, Neil; Moyer, Bruce A

    2014-01-01

    Achievement of sustainability in metal life cycles from mining of virgin ore to consumer and industrial devices to end-of-life products requires greatly increased recycling and improved processing of metals. Electronic and other high-tech products containing precious, toxic, and specialty metals usually have short lifetimes and low recycling rates. Products containing these metals generally are incinerated, discarded as waste in landfills, or dismantled in informal recycling using crude and environmentally irresponsible procedures. Low metal recycling rates coupled with increasing demand for products containing them necessitate increased mining with attendant environmental, health, energy, water, and carbon-footprint consequences. In this tutorial review, challenges to achieving metal sustainability in present high-tech society are presented; health, environmental, and economic incentives for various stakeholders to improve metal sustainability are discussed; a case for technical improvements in separations technology, especially employing molecular recognition, is given; and global consequences of continuing on the present path are examined.

  5. Sustained Silent Reading in Middle School and Its Impact on Students' Attitudes and Achievement

    ERIC Educational Resources Information Center

    Morgan, Margaret Peggy S.

    2013-01-01

    Sustained Silent Reading (SSR) is a period of time given to students to read self-selected materials during their school day. This study examines the effect of participation in a SSR program on reading attitudes and reading achievement of students as measured by the Adolescent Motivation to Read Profile (AMRP) and the Northwest Evaluation…

  6. Influence of School Climate on Students' Achievement and Teachers' Productivity for Sustainable Development

    ERIC Educational Resources Information Center

    Adeogun, A. A.; Olisaemeka, Blessing U.

    2011-01-01

    The study covers ten secondary schools in Lagos State of Nigeria. The purpose is to ascertain the relationship between school climate and student achievements and teachers' productivity for sustainable development. A total sample of 150 respondents was taken. Ten principals, seven teachers and seven students were randomly picked per school. This…

  7. Achieving Our Environmental Sustainability Goals: The Opportunities and Pitfalls of Applying Life Cycle Thinking

    EPA Science Inventory

    An increasing number of people around the world are beginning to realize that a systems approach, such as life cycle thinking, is necessary to truly achieve environmental sustainability. Without the holistic perspective that life cycle thinking provides, our actions risk leading ...

  8. Program Proposal: Certificates of Competence, Certificate of Achievement, Associate in Applied Science Degree in Sustainable Technology.

    ERIC Educational Resources Information Center

    Pezzoli, Jean A.; Ainsworth, Don

    This document proposes a program in sustainable technology at Maui Community College (Hawaii). This new career program would be designed to provide four Certificates of Competence, a Certificate of Achievement, and an Associate in Applied Science degree. The primary objectives of the program are to meet student, county, and state needs for…

  9. Ecosystem management to achieve ecological sustainability: The case of South Florida

    NASA Astrophysics Data System (ADS)

    Harwell, Mark A.; Long, John F.; Bartuska, Ann M.; Gentile, John H.; Harwell, Christine C.; Myers, Victoria; Ogden, John C.

    1996-07-01

    The ecosystems of South Florida are unique in the world. The defining features of the natural Everglades (large spatial scale, temporal patterns of water storage and sheetflow, and low nutrient levels) historically allowed a mosaic of habitats with characteristic animals. Massive hydrological alterations have halved the Everglades, and ecological sustainability requires fundamental changes in management. The US Man and the Biosphere Human-Dominated Systems Directorate is conducting a case study of South Florida using ecosystem management as a framework for exploring options for mutually dependent sustainability of society and the environment. A new methodology was developed to specify sustainability goals, characterize human factors affecting the ecosystem, and conduct scenario/consequence analyses to examine ecological and societal implications. South Florida has sufficient water for urban, agricultural, and ecological needs, but most water drains to the sea through the system of canals; thus, the issue is not competition for resources but storage and management of water. The goal is to reestablish the natural system for water quantity, timing, and distribution over a sufficient area to restore the essence of the Everglades. The societal sustainability in the Everglades Agricultural Area (EAA) is at risk because of soil degradation, vulnerability of sugar price supports, policies affecting Cuban sugar imports, and political/economic forces aligned against sugar production. One scenario suggested using the EAA for water storage while under private sugar production, thereby linking sustainability of the ecological system with societal sustainability. Further analyses are needed, but the US MAB project suggests achieving ecological sustainability consistent with societal sustainability may be feasible.

  10. Transformation of erythroid progenitors by viral and cellular tyrosine kinases.

    PubMed

    Beug, H; Schroeder, C; Wessely, O; Deiner, E; Meyer, S; Ischenko, I D; Hayman, M J

    1995-08-01

    Recently, two different normal avian erythroid progenitors were described. They differ in the receptor tyrosine kinases they express and in their ability to undergo self-renewal in culture. A common progenitor, termed stem cell factor (SCF) progenitor, expresses the receptor for avian SCF c-Kit, and undergoes short-term self-renewal when grown in the presence of avian SCF. A second progenitor, referred to as SCF/transforming growth factor-alpha progenitor, coexpresses c-Kit and the avian epidermal growth factor receptor homologue c-ErbB. These progenitors undergo sustained self-renewal when grown in the presence of transforming growth factor-alpha plus estradiol. The phenotype of the normal SCF/transforming growth factor-alpha progenitors closely corresponded to that of erythroid cells transformed by the tyrosine kinase oncogenes v-erbB or v-sea. This suggested that these cells, but not the SCF progenitors, would be the target cells for erythroblast transformation by these oncogenes. However, we demonstrate that both progenitor cells can be transformed by the v-erbB and v-sea oncogenes and also by the ligand-activated proto-oncogene product c-ErbB. We conclude that the target cell specificity of certain tyrosine kinase oncoproteins for erythroid cells is a reflection of their ability to provide signals for self-renewal that normally emanate from the endogenous c-ErbB protein. PMID:8547228

  11. Addressing China's grand challenge of achieving food security while ensuring environmental sustainability.

    PubMed

    Lu, Yonglong; Jenkins, Alan; Ferrier, Robert C; Bailey, Mark; Gordon, Iain J; Song, Shuai; Huang, Jikun; Jia, Shaofeng; Zhang, Fusuo; Liu, Xuejun; Feng, Zhaozhong; Zhang, Zhibin

    2015-02-01

    China's increasingly urbanized and wealthy population is driving a growing and changing demand for food, which might not be met without significant increase in agricultural productivity and sustainable use of natural resources. Given the past relationship between lack of access to affordable food and political instability, food security has to be given a high priority on national political agendas in the context of globalization. The drive for increased food production has had a significant impact on the environment, and the deterioration in ecosystem quality due to historic and current levels of pollution will potentially compromise the food production system in China. We discuss the grand challenges of not only producing more food but also producing it sustainably and without environmental degradation. In addressing these challenges, food production should be considered as part of an environmental system (soil, air, water, and biodiversity) and not independent from it. It is imperative that new ways of meeting the demand for food are developed while safeguarding the natural resources upon which food production is based. We present a holistic approach to both science and policy to ensure future food security while embracing the ambition of achieving environmental sustainability in China. It is a unique opportunity for China to be a role model as a new global player, especially for other emerging economies. PMID:26601127

  12. Review: Balancing Limiting Factors and Economic Drivers to Achieve Sustainable Midwestern US Agricultural Residue Feedstock Supplies

    SciTech Connect

    Wally W. Wilhelm; J. Richard Hess; Douglas L. Karlen; David J. Muth; Jane M. F. Johnson; John M. Baker; Hero T. Gollany; Jeff M. Novak; Diane E. Stott; Gary E. Varvel

    2010-10-01

    Advanced biofuels will be developed using cellulosic feedstock rather than grain or oilseed crops that can also be used for food and feed. To be sustainable, these new agronomic production systems must be economically viable without degrading soil resources. This review examines six agronomic factors that collectively define many of the limits and opportunities for harvesting crop residue for biofuel feedstock. These six “limiting factors” are discussed in relationship to economic drivers associated with harvesting corn (Zea mays L.) stover as a potential cellulosic feedstock. The limiting factors include soil organic carbon, wind and water erosion, plant nutrient balance, soil water and temperature dynamics, soil compaction, and off-site environmental impacts. Initial evaluations using the Revised Universal Soil Loss Equation 2.0 (RUSLE2) show that a single factor analysis based on simply meeting tolerable soil loss might indicate stover could be harvested sustainably, but the same analysis based on maintaining soil organic carbon shows the practice to be non-sustainable. Modifying agricultural management to include either annual or perennial cover crops is shown to meet both soil erosion and soil carbon requirements. The importance of achieving high yields and planning in a holistic manner at the landscape scale are also shown to be crucial for balancing limitations and drivers associated with renewable bioenergy production.

  13. Addressing China’s grand challenge of achieving food security while ensuring environmental sustainability

    PubMed Central

    Lu, Yonglong; Jenkins, Alan; Ferrier, Robert C.; Bailey, Mark; Gordon, Iain J.; Song, Shuai; Huang, Jikun; Jia, Shaofeng; Zhang, Fusuo; Liu, Xuejun; Feng, Zhaozhong; Zhang, Zhibin

    2015-01-01

    China’s increasingly urbanized and wealthy population is driving a growing and changing demand for food, which might not be met without significant increase in agricultural productivity and sustainable use of natural resources. Given the past relationship between lack of access to affordable food and political instability, food security has to be given a high priority on national political agendas in the context of globalization. The drive for increased food production has had a significant impact on the environment, and the deterioration in ecosystem quality due to historic and current levels of pollution will potentially compromise the food production system in China. We discuss the grand challenges of not only producing more food but also producing it sustainably and without environmental degradation. In addressing these challenges, food production should be considered as part of an environmental system (soil, air, water, and biodiversity) and not independent from it. It is imperative that new ways of meeting the demand for food are developed while safeguarding the natural resources upon which food production is based. We present a holistic approach to both science and policy to ensure future food security while embracing the ambition of achieving environmental sustainability in China. It is a unique opportunity for China to be a role model as a new global player, especially for other emerging economies. PMID:26601127

  14. What Is an Education for Sustainable Development Supposed to Achieve--A Question of What, How and Why

    ERIC Educational Resources Information Center

    Hofman, Maria

    2015-01-01

    This is a theoretical article to open the discussion of what an education for sustainable development is supposed to achieve and how teachers can help students to develop skills that might be needed in order to support a sustainable future. The focus in the article will be on education. As it is an article aiming to open this kind of discussion…

  15. Socially cooperative choices: An approach to achieving resource sustainability in the coastal zone

    NASA Astrophysics Data System (ADS)

    Crance, Colin; Draper, Dianne

    1996-03-01

    Achieving resource sustainability, particularly in the coastal zone, is complicated by a variety of interdependencies and trade-offs between economic, social, and ecological variables. Although trade-offs between each of these variables are important, this paper emphasizes the social components of resource management. In this regard a distinction is made between individual and cooperative choices. Individual choices frequently are made from a shortterm, self-interested perspective, whereas cooperative choices are made from a long-term, community and resource-sustainability perspective. Typically, when presented with a spectrum of resource management decisions, individuals have a tendency to act in a self-interested manner. Thus, cooperative benefits, such as reduced conflict and improved resource certainty, are not realized. An overview of selected aspects of social dilemma theory suggests that socially cooperative choice outcomes are attainable in coastal zone management by integrating structural and behavioral solutions in resource use decision making. Three barriers to successful integration of structural and behavioral solutions are identified as self-interest, mistrust, and variable perceptions of resource amenities. Examples from coastal zone management indicate that these barriers may be overcome using approaches such as scopereduction, co-management, community education, and local participation. The paper also provides comment on the potential benefits of integrating structural and behavioral solutions in international coastal zone management efforts.

  16. Petit receives Robert C. Cowen Award for Sustained Achievement in Science Journalism: Citation

    NASA Astrophysics Data System (ADS)

    Rademacher, Horst

    2012-01-01

    Charles W. Petit, a veteran science writer, received the 2011 Robert C. Cowan Award for Sustained Achievement in Science Journalism at the AGU Fall Meeting Honors Ceremony, held on 7 December 2011 in San Francisco, Calif. Petit covered earthquakes for the San Francisco Chronicle during the 1980s and 1990s and has recently served as "head tracker" for the Knight Science Journalism Tracker, a Massachusetts Institute of Technology-based daily blog that compiles and critiques science reporting worldwide. Petit was previously honored by AGU in 2003 when he received the David Perlman Award for an article about a new finding in oceanography. The Cowan Award, named for a former science editor of the Christian Science Monitor, is given no more than every 2 years and recognizes a journalist who has made "significant, lasting, and consistent contributions to accurate reporting or writing" on the Earth and space sciences for the general public.

  17. Petit receives Robert C. Cowen Award for Sustained Achievement in Science Journalism: Response

    NASA Astrophysics Data System (ADS)

    Petit, Charles W.

    2012-01-01

    Charles W. Petit, a veteran science writer, received the 2011 Robert C. Cowan Award for Sustained Achievement in Science Journalism at the AGU Fall Meeting Honors Ceremony, held on 7 December 2011 in San Francisco, Calif. Petit covered earthquakes for the San Francisco Chronicle during the 1980s and 1990s and has recently served as "head tracker" for the Knight Science Journalism Tracker, a Massachusetts Institute of Technology-based daily blog that compiles and critiques science reporting worldwide. Petit was previously honored by AGU in 2003 when he received the David Perlman Award for an article about a new finding in oceanography. The Cowan Award, named for a former science editor of the Christian Science Monitor, is given no more than every 2 years and recognizes a journalist who has made "significant, lasting, and consistent contributions to accurate reporting or writing" on the Earth and space sciences for the general public.

  18. Secondary Students' Reading Attitudes and Achievement in a Scaffolded Silent Reading Program versus Traditional Sustained Silent Reading

    ERIC Educational Resources Information Center

    West, Chandra Lorene

    2010-01-01

    This study explored the reading attitudes and achievement, as well as genre knowledge, of tenth, eleventh, and twelfth-grade students who participated in Scaffolded Silent Reading, Sustained Silent Reading, or a control group. The Reading and You attitude survey, Degrees of Reading Power achievement measure, and Genre Assessment were administered…

  19. Strategies Employed by Middle School Principals Successful in Increasing and Sustaining the Mathematics Achievement of African American Students

    ERIC Educational Resources Information Center

    Clark, Rebecca

    2013-01-01

    This study approaches the problem of African American mathematics achievement from a strength-based perspective, identifying practices implemented by middle school principals successful in increasing and sustaining the mathematics achievement of African American students. The study was designed to answer questions regarding both school-wide…

  20. A novel role for nuclear factor-erythroid 2 in erythroid maturation by modulation of mitochondrial autophagy.

    PubMed

    Gothwal, Monika; Wehrle, Julius; Aumann, Konrad; Zimmermann, Vanessa; Gründer, Albert; Pahl, Heike L

    2016-09-01

    We have recently demonstrated that the transcription factor nuclear factor-erythroid 2, which is critical for erythroid maturation and globin gene expression, plays an important role in the pathophysiology of myeloproliferative neoplasms. Myeloproliferative neoplasm patients display elevated levels of nuclear factor-erythroid 2 and transgenic mice overexpressing the transcription factor develop myeloproliferative neoplasm, albeit, surprisingly without erythrocytosis. Nuclear factor-erythroid 2 transgenic mice show both a reticulocytosis and a concomitant increase in iron deposits in the spleen, suggesting both enhanced erythrocyte production and increased red blood cell destruction. We therefore hypothesized that elevated nuclear factor-erythroid 2 levels may lead to increased erythrocyte destruction by interfering with organelle clearance during erythroid maturation. We have previously shown that nuclear factor-erythroid 2 overexpression delays erythroid maturation of human hematopoietic stem cells. Here we report that increased nuclear factor-erythroid 2 levels also impede murine maturation by retarding mitochondrial depolarization and delaying mitochondrial elimination. In addition, ribosome autophagy is delayed in transgenics. We demonstrate that the autophagy genes NIX and ULK1 are direct novel nuclear factor-erythroid 2 target genes, as these loci are bound by nuclear factor-erythroid 2 in chromatin immunoprecipitation assays. Moreover, Nix and Ulk1 expression is increased in transgenic mice and in granulocytes from polycythemia vera patients. This is the first report implying a role for nuclear factor-erythroid 2 in erythroid maturation by affecting autophagy. PMID:27479815

  1. Calcium Signaling Is Required for Erythroid Enucleation

    PubMed Central

    Russell, Sarah M.; Humbert, Patrick O.

    2016-01-01

    Although erythroid enucleation, the property of erythroblasts to expel their nucleus, has been known for 7ore than a century, surprisingly little is known regarding the molecular mechanisms governing this unique developmental process. Here we show that similar to cytokinesis, nuclear extrusion requires intracellular calcium signaling and signal transduction through the calmodulin (CaM) pathway. However, in contrast to cytokinesis we found that orthochromatic erythroblasts require uptake of extracellular calcium to enucleate. Together these functional studies highlight a critical role for calcium signaling in the regulation of erythroid enucleation. PMID:26731108

  2. Reproducible erythroid aplasia caused by mycophenolate mofetil.

    PubMed

    Arbeiter, K; Greenbaum, L; Balzar, E; Müller, T; Hofmeister, F; Bidmon, B; Aufricht, C

    2000-03-01

    Anemia secondary to mycophenolate mofetil (MMF) was recently described in experimental animals. A clinical association between MMF and anemia has been observed, but there are no proven reports. We describe a girl with chronic graft failure who developed erythroid aplasia under immunosuppression with MMF. She showed prompt resolution when MMF was discontinued and a recurrence of this clinical course when MMF was restarted. As re-challenge with a medication is the most definitive approach for showing a direct relationship between the drug and the side effect, this case clearly demonstrates that MMF can cause erythroid aplasia. PMID:10752755

  3. Calcium Signaling Is Required for Erythroid Enucleation.

    PubMed

    Wölwer, Christina B; Pase, Luke B; Russell, Sarah M; Humbert, Patrick O

    2016-01-01

    Although erythroid enucleation, the property of erythroblasts to expel their nucleus, has been known for 7ore than a century, surprisingly little is known regarding the molecular mechanisms governing this unique developmental process. Here we show that similar to cytokinesis, nuclear extrusion requires intracellular calcium signaling and signal transduction through the calmodulin (CaM) pathway. However, in contrast to cytokinesis we found that orthochromatic erythroblasts require uptake of extracellular calcium to enucleate. Together these functional studies highlight a critical role for calcium signaling in the regulation of erythroid enucleation. PMID:26731108

  4. Modulation of retinoblastoma gene in normal adult hematopoiesis: peak expression and functional role in advanced erythroid differentiation.

    PubMed Central

    Condorelli, G L; Testa, U; Valtieri, M; Vitelli, L; De Luca, A; Barberi, T; Montesoro, E; Campisi, S; Giordano, A; Peschle, C

    1995-01-01

    The retinoblastoma (RB) gene specifies a nuclear phosphoprotein (pRb 105), which is a prototype tumor suppressor inactivated in a variety of human tumors. Recent studies suggest that RB is also involved in embryonic development of murine central nervous and hematopoietic systems. We have investigated RB expression and function in human adult hematopoiesis--i.e., in liquid suspension culture of purified quiescent hematopoietic progenitor cells (HPCs) induced by growth factor stimulus to proliferation and unilinage differentiation/maturation through the erythroid or granulocytic lineage. In the initial HPC differentiation stages, the RB gene is gradually induced at the mRNA and protein level in both erythroid and granulopoietic cultures. In late HPC differentiation and then precursor maturation, RB gene expression is sustained in the erythroid lineage, whereas it is sharply downmodulated in the granulocytic series. Functional studies were performed by treatment of HPC differentiation culture with phosphorothioate antisense oligomer targeting Rb mRNA; coherent with the expression pattern, oligomer treatment of late HPCs causes a dose-dependent and selective inhibition of erythroid colony formation. These observations suggest that the RB gene plays an erythroid- and stage-specific functional role in normal adult hematopoiesis, particularly at the level of late erythroid HPCs. Images Fig. 2 Fig. 3 Fig. 4 PMID:7761404

  5. Sustainability.

    PubMed

    Chang, Chein-Chi; DiGiovanni, Kimberly; Mei, Ying; Wei, Li

    2016-10-01

    This review on Sustainability covers selected 2015 publications on the focus of Sustainability. It is divided into the following sections : • Sustainable water and wastewater utilities • Sustainable water resources management • Stormwater and green infrastructure • Sustainability in wastewater treatment • Life cycle assessment (LCA) applications • Sustainability and energy in wastewater industry, • Sustainability and asset management. PMID:27620092

  6. Achieving and sustaining profound institutional change in healthcare: case study using neo-institutional theory.

    PubMed

    Macfarlane, Fraser; Barton-Sweeney, Cathy; Woodard, Fran; Greenhalgh, Trisha

    2013-03-01

    Change efforts in healthcare sometimes have an ambitious, whole-system remit and seek to achieve fundamental changes in norms and organisational culture rather than (or as well as) restructuring the service. Long-term evaluation of such initiatives is rarely undertaken. We report a secondary analysis of data from an evaluation of a profound institutional change effort in London, England, using a mixed-method longitudinal case study design. The service had received £15 million modernisation funding in 2004, covering multiple organisations and sectors and overseen by a bespoke management and governance infrastructure that was dismantled in 2008. In 2010-11, we gathered data (activity statistics, documents, interviews, questionnaires, site visits) and compared these with data from 2003 to 2008. Data analysis was informed by neo-institutional theory, which considers organisational change as resulting from the material-resource environment and three 'institutional pillars' (regulative, normative and cultural-cognitive), enacted and reproduced via the identities, values and activities of human actors. Explaining the long-term fortunes of the different components of the original programme and their continuing adaptation to a changing context required attention to all three of Scott's pillars and to the interplay between macro institutional structures and embedded human agency. The paper illustrates how neo-institutional theory (which is typically used by academics to theorise macro-level changes in institutional structures over time) can also be applied at a more meso level to inform an empirical analysis of how healthcare organisations achieve change and what helps or hinders efforts to sustain those changes. PMID:23415586

  7. Distinct foods with smaller unit would be an effective approach to achieve sustainable weight loss.

    PubMed

    Chang, Un Jae; Suh, Hyung Joo; Yang, Sun Ok; Hong, Yang Hee; Kim, Young Suk; Kim, Jin Man; Jung, Eun Young

    2012-01-01

    We studied the effects of food type and food unit size on food intake and satiety using fried rice mixed with Kimchi in healthy Korean young women (n=31). Amorphous fried rice (1st week), distinct large fried rice balls (100 g/unit, 2nd week) and distinct small fried rice balls (20 g/unit, 3rd week) were served in the same content and volume (500 g). Subjects ate significantly (p<.001) less distinct large fried rice balls (243.5 g) compared to amorphous fried rice (317.2 g). Despite consuming more amorphous fried rice, subjects did not feel significantly fuller after eating amorphous fried rice compared to distinct large fried rice balls. When distinct fried rice balls were served as smaller unit, subjects ate significantly less them (small unit; 190.6 g vs. large unit; 243.5 g, p<.01). Although subjects ate more distinct fried rice balls provided as large unit, they rated similar satiety and hunger levels for distinct small and distinct large fried rice balls. In conclusion, we propose that distinct foods with smaller unit would be an effective approach to achieve sustainable weight loss. PMID:22177403

  8. Sustainability.

    PubMed

    Chang, Chein-Chi; DiGiovanni, Kimberly; Zhang, Gong; Yang, Xiahua; You, Shao-Hong

    2015-10-01

    This review on Sustainability covers selected 2014 publications on the focus of the following sections: • Sustainable water and wastewater utilities • Sustainable water resources management • Stormwater and green infrastructure • Sustainability in wastewater treatment • Life cycle assessment (LCA) applications • Sustainability and energy in wastewater industry, • Sustainability and asset management. PMID:26420087

  9. Achieving and Sustaining Automated Health Data Linkages for Learning Systems: Barriers and Solutions

    PubMed Central

    Van Eaton, Erik G.; Devlin, Allison B.; Devine, Emily Beth; Flum, David R.; Tarczy-Hornoch, Peter

    2014-01-01

    challenges of idiosyncratic EHR implementations required each hospital to devote more IT resources than were predicted. Cost savings did not meet projections because of the increased IT resource requirements and a different source of lowered chart review costs. Discussion: CERTAIN succeeded in recruiting unaffiliated hospitals into the Automation Project to create an enhanced registry to achieve AHRQ goals. This case report describes several distinct barriers to central data aggregation for QI and CER across unaffiliated hospitals: (1) competition for limited on-site IT expertise, (2) concerns about data use for QI versus research, (3) restrictions on data automation to a defined subset of patients, and (4) unpredictable resource needs because of idiosyncrasies among unaffiliated hospitals in how EHR data are coded, stored, and made available for transmission—even between hospitals using the same vendor’s EHR. Therefore, even a fully optimized automation infrastructure would still not achieve complete automation. The Automation Project was unable to align sufficiently with internal hospital objectives, so it could not show a compelling case for sustainability. PMID:25848606

  10. Concepts for Life Cycle Cost Control Required to Achieve Space Transportation Affordability and Sustainability

    NASA Technical Reports Server (NTRS)

    Rhodes, Russel E.; Zapata, Edgar; Levack, Daniel J. H.; Robinson, John W.; Donahue, Benjamin B.

    2009-01-01

    Cost control must be implemented through the establishment of requirements and controlled continually by managing to these requirements. Cost control of the non-recurring side of life cycle cost has traditionally been implemented in both commercial and government programs. The government uses the budget process to implement this control. The commercial approach is to use a similar process of allocating the non-recurring cost to major elements of the program. This type of control generally manages through a work breakdown structure (WBS) by defining the major elements of the program. If the cost control is to be applied across the entire program life cycle cost (LCC), the approach must be addressed very differently. A functional breakdown structure (FBS) is defined and recommended. Use of a FBS provides the visibifity to allow the choice of an integrated solution reducing the cost of providing many different elements of like function. The different functional solutions that drive the hardware logistics, quantity of documentation, operational labor, reliability and maintainability balance, and total integration of the entire system from DDT&E through the life of the program must be fully defined, compared, and final decisions made among these competing solutions. The major drivers of recurring cost have been identified and are presented and discussed. The LCC requirements must be established and flowed down to provide control of LCC. This LCC control will require a structured rigid process similar to the one traditionally used to control weight/performance for space transportation systems throughout the entire program. It has been demonstrated over the last 30 years that without a firm requirement and methodically structured cost control, it is unlikely that affordable and sustainable space transportation system LCC will be achieved.

  11. The Sustainability of Reading Recovery Intervention on Reading Achievement of Students Identified as At-Risk for Early Reading Failure

    ERIC Educational Resources Information Center

    Harley, Anne J.

    2012-01-01

    The purpose of this study was to determine the impact and sustainability of successfully discontinued first grade Reading Recovery students as compared to non-Reading Recovery students in reading achievement measures as third graders. Schools are facing the unprecedented challenge to ensure reading success for all students by the end of second…

  12. In Pursuit of Sustained Achievement: A Case Study of One At-Risk School's Efforts to Change Behaviors

    ERIC Educational Resources Information Center

    Sorvig, Carol A.

    2010-01-01

    Sustained achievement remains out of reach for most Title I schools. While there are many programs and examples of schools touting improved performance, there are precious few that are able to maintain that improved performance over time. This case study examined the characteristics of changes made at one Colorado Title I elementary school that…

  13. Lipophilic nalmefene prodrugs to achieve a one-month sustained release.

    PubMed

    Gaekens, Tim; Guillaume, Michel; Borghys, Herman; De Zwart, Loeckie L; de Vries, Ronald; Embrechts, Roger C A; Vermeulen, An; Megens, Anton A H P; Leysen, Josée E; Herdewijn, Piet; Annaert, Pieter P; Atack, John R

    2016-06-28

    Nalmefene is an opioid antagonist which as a once-a-day tablet formulation has recently been approved for reducing ethanol intake in alcoholic subjects. In order to address the compliance issue in this patient population, a number of potential nalmefene prodrugs were synthesized with the aim of providing a formulation that could provide plasma drug concentrations in the region of 0.5-1.0ng/mL for a one-month period when dosed intramuscular to dogs or minipigs. In an initial series of studies, three different lipophilic nalmefene derivatives were evaluated: the palmitate (C16), the octadecyl glutarate diester (C18-C5) and the decyl carbamate (CB10). They were administered intramuscularly to dogs in a sesame oil solution at a dose of 1mg-eq. nalmefene/kg. The decyl carbamate was released relatively quickly from the oil depot and its carbamate bond was too stable to be used as a prodrug. The other two derivatives delivered a fairly constant level of 0.2-0.3ng nalmefene/mL plasma for one month and since there was no significant difference between these two, the less complex palmitate monoester was chosen to demonstrate that dog plasma nalmefene concentrations were dose-dependent at 1, 5 and 20mg-eq. nalmefene/kg. In a second set of experiments, the effect of the chain length of the fatty acid monoester promoieties was examined. The increasingly lipophilic octanoate (C8), decanoate (C10) and dodecanoate (C12) derivatives were evaluated in dogs and in minipigs, at a dose of 5mg-eq. nalmefene/kg and plasma nalmefene concentrations were measured over a four-week period. The pharmacokinetic profiles were very similar in both species with Cmax decreasing and Tmax increasing with increasing fatty acid chain length and the target plasma concentrations (0.5-1.0ng/mL over a month-long period) were achieved with the dodecanoate (C12) prodrug. These data therefore demonstrate that sustained plasma nalmefene concentrations can be achieved in both dog and minipig using nalmefene

  14. Achieving Campus Sustainability: Top-Down, Bottom-Up, or Neither?

    ERIC Educational Resources Information Center

    Brinkhurst, Marena; Rose, Peter; Maurice, Gillian; Ackerman, Josef Daniel

    2011-01-01

    Purpose: The dynamics of organizational change related to environmental sustainability on university campuses are examined in this article. Whereas case studies of campus sustainability efforts tend to classify leadership as either "top-down" or "bottom-up", this classification neglects consideration of the leadership roles of the institutional…

  15. Isolation and in vitro differentiation of human erythroid precursor cells.

    PubMed

    Kim, H C; Marks, P A; Rifking, R A; Maniatis, G M; Bank, A

    1976-05-01

    There is decreased beta-globin production in beta-thalassemic reticulocytes and nucleated erythroid cells. In this study, we have examined whether unbalanced globin synthesis is expressed at all stages of human erythroid cell maturation. In order to determine the pattern of globin synthesis in early erythroid cells during erythroid cell maturation, an in vitro culture system using human bone marrow erythroid precursor cells has been developed. Early erythroid precursor cells (proerythroblasts and basophilic erythroblasts) have been isolated from nonthalassemic and thalassemic human bone marrows by lysing more mature erythroid cells, using complement and a rabbit antiserum prepared against normal human red cells. In the presence of erythropoietin, differentiation and proliferation of erythroid cells in demonstrable in liquid suspension culture for 24-48 hr, as determined by morphological criteria and by an increase in globin synthesis. The ratio of alpha- to beta-globin chain synthesis in nonthalassemic cells in approximately 1 at all stages of erythroid cell differentiation during culture. In cells from four patients with homozygous beta- thalassemia there is decreased beta-globin synthesis compared to alpha-globin synthesis, both in early erythroid precursor cells and during their maturation in culture. These findings indicate that unbalanced globin chain synthesis is expressed at all stages of red cell maturation in homozygous beta-thalassemia. PMID:1260133

  16. Early stage design decisions: the way to achieve sustainable buildings at lower costs.

    PubMed

    Bragança, Luís; Vieira, Susana M; Andrade, Joana B

    2014-01-01

    The construction industry attempts to produce buildings with as lower environmental impact as possible. However, construction activities still greatly affect environment; therefore, it is necessary to consider a sustainable project approach based on its performance. Sustainability is an important issue to consider in design, not only due to environmental concerns but also due to economic and social matters, promoting architectural quality and economic advantages. This paper aims to identify the phases through which a design project should be developed, emphasising the importance and ability of earlier stages to influence sustainability, performance, and life cycle cost. Then, a selection of sustainability key indicators, able to be used at the design conceptual phase and able to start predicting environmental sustainability performance of buildings is presented. The output of this paper aimed to enable designers to compare and evaluate the consequences of different design solutions, based on preliminary data, and facilitate the collaboration between stakeholders and clients and eventually yield a sustainable and high performance building throughout its life cycle. PMID:24578630

  17. Significant Increase in Ecosystem C Can Be Achieved with Sustainable Forest Management in Subtropical Plantation Forests

    PubMed Central

    Wei, Xiaohua; Blanco, Juan A.

    2014-01-01

    Subtropical planted forests are rapidly expanding. They are traditionally managed for intensive, short-term goals that often lead to long-term yield decline and reduced carbon sequestration capacity. Here we show how it is possible to increase and sustain carbon stored in subtropical forest plantations if management is switched towards more sustainable forestry. We first conducted a literature review to explore possible management factors that contribute to the potentials in ecosystem C in tropical and subtropical plantations. We found that broadleaves plantations have significantly higher ecosystem C than conifer plantations. In addition, ecosystem C increases with plantation age, and reaches a peak with intermediate stand densities of 1500–2500 trees ha−1. We then used the FORECAST model to simulate the regional implications of switching from traditional to sustainable management regimes, using Chinese fir (Cunninghamia lanceolata) plantations in subtropical China as a study case. We randomly simulated 200 traditional short-rotation pure stands and 200 sustainably-managed mixed Chinese fir – Phoebe bournei plantations, for 120 years. Our results showed that mixed, sustainably-managed plantations have on average 67.5% more ecosystem C than traditional pure conifer plantations. If all pure plantations were gradually transformed into mixed plantations during the next 10 years, carbon stocks could rise in 2050 by 260.22 TgC in east-central China. Assuming similar differences for temperate and boreal plantations, if sustainable forestry practices were applied to all new forest plantation types in China, stored carbon could increase by 1,482.80 TgC in 2050. Such an increase would be equivalent to a yearly sequestration rate of 40.08 TgC yr−1, offsetting 1.9% of China’s annual emissions in 2010. More importantly, this C increase can be sustained in the long term through the maintenance of higher amounts of soil organic carbon and the production of timber

  18. Erythropoietin guides multipotent hematopoietic progenitor cells toward an erythroid fate

    PubMed Central

    Grover, Amit; Mancini, Elena; Moore, Susan; Mead, Adam J.; Atkinson, Deborah; Rasmussen, Kasper D.; O’Carroll, Donal; Jacobsen, Sten Eirik W.

    2014-01-01

    The erythroid stress cytokine erythropoietin (Epo) supports the development of committed erythroid progenitors, but its ability to act on upstream, multipotent cells remains to be established. We observe that high systemic levels of Epo reprogram the transcriptomes of multi- and bipotent hematopoietic stem/progenitor cells in vivo. This induces erythroid lineage bias at all lineage bifurcations known to exist between hematopoietic stem cells (HSCs) and committed erythroid progenitors, leading to increased erythroid and decreased myeloid HSC output. Epo, therefore, has a lineage instructive role in vivo, through suppression of non-erythroid fate options, demonstrating the ability of a cytokine to systematically bias successive lineage choices in favor of the generation of a specific cell type. PMID:24493804

  19. Pulmonary liposomal formulations encapsulated procaterol hydrochloride by a remote loading method achieve sustained release and extended pharmacological effects.

    PubMed

    Tahara, Kohei; Tomida, Hiromasa; Ito, Yousuke; Tachikawa, Suguru; Onodera, Risako; Tanaka, Hiroyuki; Tozuka, Yuichi; Takeuchi, Hirofumi

    2016-05-30

    Drug inhalation provides localized drug therapy for respiratory diseases. However, the therapeutic efficacy of inhaled drugs is limited by rapid clearance from the lungs. Small hydrophilic compounds have short half-lives to systemic absorption. We developed a liposomal formulation as a sustained-release strategy for pulmonary delivery of procaterol hydrochloride (PRO), a short-acting pulmonary β2-agonist for asthma treatment. After PRO-loaded liposomes were prepared using a pH gradient (remote loading) method, 100-nm liposomes improved residence times of PRO in the lungs. PRO encapsulation efficiency and release profiles were examined by screening several liposomal formulations of lipid, cholesterol, and inner phase. Although PRO loading was not achieved using the conventional hydration method, PRO encapsulation efficiency was >60% using the pH gradient method. PRO release from liposomes was sustained for several hours depending on liposomal composition. The liposomal formulation effects on the PRO behavior in rat lungs were evaluated following pulmonary administration in vivo. Sustained PRO release was achieved using simplified egg phosphatidylcholine (EPC)/cholesterol (8/1) liposome in vitro, and greater PRO remnants were observed in rat lungs following pulmonary administration. Extended pharmacological PRO effects were observed for 120min in a histamine-induced bronchoconstriction guinea pig model. We indicated the simplified EPC/cholesterol liposome potential as a controlled-release PRO carrier for pulmonary administration. PMID:27012982

  20. Bmi1 promotes erythroid development through regulating ribosome biogenesis

    PubMed Central

    Gao, Rui; Chen, Sisi; Kobayashi, Michihiro; Yu, Hao; Zhang, Yingchi; Wan, Yang; Young, Sara K.; Soltis, Anthony; Yu, Ming; Vemula, Sasidhar; Fraenkel, Ernest; Cantor, Alan; Antipin, Yevgeniy; Xu, Yang; Yoder, Mervin C.; Wek, Ronald C.; Ellis, Steven R.; Kapur, Reuben; Zhu, Xiaofan; Liu, Yan

    2015-01-01

    While Polycomb group protein Bmi1 is important for stem cell maintenance, its role in lineage commitment is largely unknown. We have identified Bmi1 as a novel regulator of erythroid development. Bmi1 is highly expressed in mouse erythroid progenitor cells and its deficiency impairs erythroid differentiation. BMI1 is also important for human erythroid development. Furthermore, we discovered that loss of Bmi1 in erythroid progenitor cells results in down-regulation of transcription of multiple ribosomal protein genes and impaired ribosome biogenesis. Bmi1 deficiency stabilizes p53 protein, leading to upregulation of p21 expression and subsequent G0/G1 cell cycle arrest. Genetic inhibition of p53 activity rescues the erythroid defects seen in the Bmi1 null mice, demonstrating that a p53-dependent mechanism underlies the pathophysiology of the anemia. Mechanistically, Bmi1 is associated with multiple ribosomal protein genes and may positively regulate their expression in erythroid progenitor cells. Thus, Bmi1 promotes erythroid development, at least in part through regulating ribosome biogenesis. Ribosomopathies are human disorders of ribosome dysfunction, including diamond blackfan anemia (DBA) and 5q- syndrome, in which genetic abnormalities cause impaired ribosome biogenesis, resulting in specific clinical phenotypes. We observed that BMI1 expression in human hematopoietic stem and progenitor cells (HSPCs) from patients with DBA is correlated with the expression of some ribosomal protein genes, suggesting that BMI1 deficiency may play a pathological role in DBA and other ribosomopathies. PMID:25385494

  1. Bmi1 promotes erythroid development through regulating ribosome biogenesis.

    PubMed

    Gao, Rui; Chen, Sisi; Kobayashi, Michihiro; Yu, Hao; Zhang, Yingchi; Wan, Yang; Young, Sara K; Soltis, Anthony; Yu, Ming; Vemula, Sasidhar; Fraenkel, Ernest; Cantor, Alan; Antipin, Yevgeniy; Xu, Yang; Yoder, Mervin C; Wek, Ronald C; Ellis, Steven R; Kapur, Reuben; Zhu, Xiaofan; Liu, Yan

    2015-03-01

    While Polycomb group protein Bmi1 is important for stem cell maintenance, its role in lineage commitment is largely unknown. We have identified Bmi1 as a novel regulator of erythroid development. Bmi1 is highly expressed in mouse erythroid progenitor cells and its deficiency impairs erythroid differentiation. BMI1 is also important for human erythroid development. Furthermore, we discovered that loss of Bmi1 in erythroid progenitor cells results in decreased transcription of multiple ribosomal protein genes and impaired ribosome biogenesis. Bmi1 deficiency stabilizes p53 protein, leading to upregulation of p21 expression and subsequent G0/G1 cell cycle arrest. Genetic inhibition of p53 activity rescues the erythroid defects seen in the Bmi1 null mice, demonstrating that a p53-dependent mechanism underlies the pathophysiology of the anemia. Mechanistically, Bmi1 is associated with multiple ribosomal protein genes and may positively regulate their expression in erythroid progenitor cells. Thus, Bmi1 promotes erythroid development, at least in part through regulating ribosome biogenesis. Ribosomopathies are human disorders of ribosome dysfunction, including Diamond-Blackfan anemia (DBA) and 5q- syndrome, in which genetic abnormalities cause impaired ribosome biogenesis, resulting in specific clinical phenotypes. We observed that BMI1 expression in human hematopoietic stem and progenitor cells from patients with DBA is correlated with the expression of some ribosomal protein genes, suggesting that BMI1 deficiency may play a pathological role in DBA and other ribosomopathies. PMID:25385494

  2. Visual sustained attention and numerosity sensitivity correlate with math achievement in children.

    PubMed

    Anobile, Giovanni; Stievano, Paolo; Burr, David C

    2013-10-01

    In this study, we investigated in school-age children the relationship among mathematical performance, the perception of numerosity (discrimination and mapping to number line), and sustained visual attention. The results (on 68 children between 8 and 11 years of age) show that attention and numerosity perception predict math scores but not reading performance. Even after controlling for several variables, including age, gender, nonverbal IQ, and reading accuracy, attention remained correlated with math skills and numerosity discrimination. These findings support previous reports showing the interrelationship between visual attention and both numerosity perception and math performance. It also suggests that attentional deficits may be implicated in disturbances such as developmental dyscalculia. PMID:23933254

  3. The Knowledge Base for Achieving the Sustainable Development Goal Targets on Water Supply, Sanitation and Hygiene.

    PubMed

    Hutton, Guy; Chase, Claire

    2016-01-01

    Safe drinking water, sanitation, and hygiene (WASH) are fundamental to an improved standard of living. Globally, 91% of households used improved drinking water sources in 2015, while for improved sanitation it is 68%. Wealth disparities are stark, with rural populations, slum dwellers and marginalized groups lagging significantly behind. Service coverage is significantly lower when considering the new water and sanitation targets under the sustainable development goals (SDGs) which aspire to a higher standard of 'safely managed' water and sanitation. Lack of access to WASH can have an economic impact as much as 7% of Gross Domestic Product, not including the social and environmental consequences. Research points to significant health and socio-economic consequences of poor nutritional status, child growth and school performance caused by inadequate WASH. Groundwater over-extraction and pollution of surface water bodies have serious impacts on water resource availability and biodiversity, while climate change exacerbates the health risks of water insecurity. A significant literature documents the beneficial impacts of WASH interventions, and a growing number of impact evaluation studies assess how interventions are optimally financed, implemented and sustained. Many innovations in behavior change and service delivery offer potential for scaling up services to meet the SDGs. PMID:27240389

  4. The Knowledge Base for Achieving the Sustainable Development Goal Targets on Water Supply, Sanitation and Hygiene

    PubMed Central

    Hutton, Guy; Chase, Claire

    2016-01-01

    Safe drinking water, sanitation, and hygiene (WASH) are fundamental to an improved standard of living. Globally, 91% of households used improved drinking water sources in 2015, while for improved sanitation it is 68%. Wealth disparities are stark, with rural populations, slum dwellers and marginalized groups lagging significantly behind. Service coverage is significantly lower when considering the new water and sanitation targets under the sustainable development goals (SDGs) which aspire to a higher standard of ‘safely managed’ water and sanitation. Lack of access to WASH can have an economic impact as much as 7% of Gross Domestic Product, not including the social and environmental consequences. Research points to significant health and socio-economic consequences of poor nutritional status, child growth and school performance caused by inadequate WASH. Groundwater over-extraction and pollution of surface water bodies have serious impacts on water resource availability and biodiversity, while climate change exacerbates the health risks of water insecurity. A significant literature documents the beneficial impacts of WASH interventions, and a growing number of impact evaluation studies assess how interventions are optimally financed, implemented and sustained. Many innovations in behavior change and service delivery offer potential for scaling up services to meet the SDGs. PMID:27240389

  5. Sublethal radiation injury uncovers a functional transition during erythroid maturation

    PubMed Central

    Peslak, Scott A.; Wenger, Jesse; Bemis, Jeffrey C.; Kingsley, Paul D.; Frame, Jenna M.; Koniski, Anne D.; Chen, Yuhchyau; Williams, Jacqueline P.; McGrath, Kathleen E.; Dertinger, Stephen D.; Palis, James

    2012-01-01

    Objective Clastogenic injury of the erythroid lineage results in anemia, reticulocytopenia, and transient appearance of micronucleated reticulocytes (MN-RET). However, the MN-RET dose-response in murine models is only linear to 2 Gy total body irradiation (TBI) and paradoxically decreases at higher exposures, suggesting complex radiation effects on erythroid intermediates. To better understand this phenomenon, we investigated the kinetics and apoptotic response of the erythron to sublethal radiation injury. Materials and Methods We analyzed the response to 1 and 4 Gy TBI of erythroid progenitors and precursors using colony assays and imaging flow cytometry (IFC), respectively. We also investigated cell cycling and apoptotic gene expression of the steady-state erythron. Results Following 1 Gy TBI, erythroid progenitors and precursors were partially depleted. In contrast, essentially all bone marrow erythroid progenitors and precursors were lost within two days following 4 Gy irradiation. IFC analysis revealed preferential loss of phenotypic erythroid colony-forming units (CFU-E) and proerythroblasts immediately following sublethal irradiation. Furthermore, these populations underwent radiation-induced apoptosis, without changes in steady-state cellular proliferation, at much higher frequencies than later-stage erythroid precursors. Primary erythroid precursor maturation is associated with marked Bcl-xL upregulation and Bax and Bid down-regulation. Conclusions MN-RET loss following higher sublethal radiation exposures results from rapid depletion of erythroid progenitors and precursors. This injury reveals that CFU-E and proerythroblasts constitute a particularly proapoptotic compartment within the erythron. We conclude that the functional transition of primary proerythroblasts to later-stage erythroid precursors is characterized by a shift from a pro-apoptotic to an anti-apoptotic phenotype. PMID:21291953

  6. Rock on Cafe: achieving sustainable systems changes in school lunch programs.

    PubMed

    Johnston, Yvonne; Denniston, Ray; Morgan, Molly; Bordeau, Mark

    2009-04-01

    The rising rate of overweight poses a significant threat to the health of children. Because roughly one third of a child's dietary intake occurs during school hours and because both health and academic outcomes have been linked to children's nutrition, school nutrition policies and programs have been identified as a key area for intervention. This article describes the components, processes, and initial successes of a grassroots effort and innovative project to improve the nutritional quality of the School Lunch Program through a sustainable systems intervention and policy change across a regional area of upstate New York. The Rock on Cafe intervention was partially funded by the Steps to a Healthier New York program and promises to be a model for creating a school environment that supports healthy dietary behaviors among children. PMID:19454756

  7. Challenges to Achieving Sustainable Sanitation in Informal Settlements of Kigali, Rwanda

    PubMed Central

    Tsinda, Aime; Abbott, Pamela; Pedley, Steve; Charles, Katrina; Adogo, Jane; Okurut, Kenan; Chenoweth, Jonathan

    2013-01-01

    Like most cities in developing countries, Kigali is experiencing rapid urbanisation leading to an increase in the urban population and rapid growth in the size and number of informal settlements. More than 60% of the city’s population resides in these settlements, where they experience inadequate and poor quality urban services including sanitation. This article discusses the issues and constraints related to the provision of sustainable sanitation in the informal settlements in Kigali. Two informal settlements (Gatsata and Kimisagara) were selected for the study, which used a mixed method approach for data collection. The research found that residents experienced multiple problems because of poor sanitation and that the main barrier to improved sanitation was cost. Findings from this study can be used by the city authorities in the planning of effective sanitation intervention strategies for communities in informal settlements. PMID:24336021

  8. Controlling interlayer diffusion to achieve sustained, multiagent delivery from layer-by-layer thin films

    PubMed Central

    Wood, Kris C.; Chuang, Helen F.; Batten, Robert D.; Lynn, David M.; Hammond, Paula T.

    2006-01-01

    We present the fabrication of conformal, hydrolytically degradable thin films capable of administering sustained, multiagent release profiles. Films are constructed one molecular layer at a time by using the layer-by-layer, directed-deposition technique; the subsequent hydrolytic surface erosion of these systems results in the release of incorporated materials in a sequence that reflects their relative positions in the film. The position of each species is determined by its ability to diffuse throughout the film architecture, and, as such, the major focus of this work is to define strategies that physically block interlayer diffusion during assembly to create multicomponent, stratified films. By using a series of radiolabeled polyelectrolytes as experimental probes, we show that covalently crosslinked barriers can effectively block interlayer diffusion, leading to compartmentalized structures, although even very large numbers of ionically crosslinked (degradable or nondegradable) barrier layers cannot block interlayer diffusion. By using these principles, we designed degradable films capable of extended release as well as both parallel and serial multiagent release. The ability to fabricate multicomponent thin films with nanoscale resolution may lead to a host of new materials and applications. PMID:16801543

  9. Erythroid Heme Biosynthesis and Its Disorders

    PubMed Central

    Meissner, Peter N.

    2013-01-01

    Heme, which is composed of iron and the small organic molecule protoporphyrin, is an essential component of hemoglobin as well as a variety of physiologically important hemoproteins. During erythropoiesis, heme synthesis is induced before, and is essential for, globin synthesis. Although all cells possess the ability to synthesize heme, there are distinct differences between regulation of the pathway in developing erythroid cells and all other types of cells. Disorders that compromise the ability of the developing red cell to synthesize heme can have profound medical implications. The biosynthetic pathway for heme and key regulatory features are reviewed herein, along with specific human genetic disorders that arise from defective heme synthesis such as X-linked sideroblastic anemia and erythropoietic protoporphyria. PMID:23471474

  10. Suppression of erythroid development in vitro by Plasmodium vivax

    PubMed Central

    2012-01-01

    Background Severe anaemia due to dyserythropoiesis has been documented in patients infected with Plasmodium vivax, however the mechanism responsible for anaemia in vivax malaria is poorly understood. In order to better understand the role of P. vivax infection in anaemia the inhibition of erythropoiesis using haematopoietic stem cells was investigated. Methods Haematopoietic stem cells/CD34+ cells, isolated from normal human cord blood were used to generate growing erythroid cells. Exposure of CD34+ cells and growing erythroid cells to P. vivax parasites either from intact or lysed infected erythrocytes (IE) was examined for the effect on inhibition of cell development compared with untreated controls. Results Both lysed and intact infected erythrocytes significantly inhibited erythroid growth. The reduction of erythroid growth did not differ significantly between exposure to intact and lysed IE and the mean growth relative to unexposed controls was 59.4 ± 5.2 for lysed IE and 57 ± 8.5% for intact IE. Interestingly, CD34+ cells/erythroid progenitor cells were susceptible to the inhibitory effect of P. vivax on cell expansion. Exposure to P. vivax also inhibited erythroid development, as determined by the reduced expression of glycophorin A (28.1%) and CD 71 (43.9%). Moreover, vivax parasites perturbed the division of erythroid cells, as measured by the Cytokinesis Block Proliferation Index, which was reduced to 1.35 ± 0.05 (P-value < 0.01) from a value of 2.08 ± 0.07 in controls. Neither TNF-a nor IFN-g was detected in the culture medium of erythroid cells treated with P. vivax, indicating that impaired erythropoiesis was independent of these cytokines. Conclusions This study shows for the first time that P. vivax parasites inhibit erythroid development leading to ineffective erythropoiesis and highlights the potential of P. vivax to cause severe anaemia. PMID:22624872

  11. Does the law stymie the science? The role of law in achieving sustainable groundwater management

    NASA Astrophysics Data System (ADS)

    Allan, A.

    2012-04-01

    Legal frameworks for the management of groundwater evolved in an environment where scientific understanding of the resource was sketchy. As hydrogeological knowledge has improved over time, the law has often failed to catch up and enforcement of those laws that are in place has proved difficult. Consequently, groundwater in many countries is still managed by inadequate regimes that are unable to effectively integrate the impacts of land use management and surface water interactions. The Water Framework Directive and its associated Groundwater Directive require the integrated management of both ground and surface waters, but on a global level, this is unusual. Institutional frameworks often perpetuate this split, and the legal regime for the management of transboundary shared aquifers is a work in progress. Both national and international frameworks encourage a race to over-exploit groundwater resources. Symptomatic of the problems currently seen in groundwater management is a widespread inability to adapt to changing climate and environmental conditions. Users may be granted unchangeable rights of use in perpetuity, and the impacts of aquifer over-exploitation on dependent ecosystems may be ignored. There are therefore significant barriers to the application of existing science in many countries, and this seriously jeopardises efforts to sustainably manage groundwater. This presentation will assess current developments in the laws relating to the use of groundwater around the world, highlighting case studies from India, Australia and the USA, and assessing the implementation of the Groundwater Directive in selected European countries (in work derived from the EU-funded GENESIS project). It will also examine the legal architecture relating to international shared aquifers, and the extent to which it can cope with national groundwater use patterns that will shift in response to climate change and its consequences.

  12. Quaternary Aquifer of the North China Plain-assessing and achieving groundwater resource sustainability

    NASA Astrophysics Data System (ADS)

    Foster, Stephen; Garduno, Hector; Evans, Richard; Olson, Doug; Tian, Yuan; Zhang, Weizhen; Han, Zaisheng

    The Quaternary Aquifer of the North China Plain is one of the world's largest aquifer systems and supports an enormous exploitation of groundwater, which has reaped large socio-economic benefits in terms of grain production, farming employment and rural poverty alleviation, together with urban and industrial water-supply provision. Both population and economic activity have grown markedly in the past 25 years. Much of this has been heavily dependent upon groundwater resource development, which has encountered increasing difficulties in recent years primarily as a result of aquifer depletion and related phenomena. This paper focuses upon the hydrogeologic and socio-economic diagnosis of these groundwater resource issues, and identifies strategies to improve groundwater resource sustainability. L'aquifère Quaternaire de la Plaine du Nord de la Chine est l'un des plus grands systèmes aquifères du monde; il permet une exploitation énorme d'eau souterraine, qui a permis des très importants bénéfices socio-économiques en terme de production de céréales, d'emplois ruraux et de réduction de la pauvreté rurale, en même temps que l'approvisionnement en eau potable et pour l'industrie. La population comme l'activité économique ont remarquablement augmenté au cours de ces 25 dernières années. Elles ont été sous la forte dépendance du développement de la ressource en eau souterraine, qui a rencontré des difficultés croissantes ces dernières années, du fait du rabattement de l'aquifère et des phénomènes associés. Cet article est consacré aux diagnostiques hydrogéologique et socio-économique des retombées de cette ressource en eau souterraine; il identifie les stratégies pour améliorer la pérennité des ressources en eau souterraine. El acuífero cuaternario de la Llanura Septentrional de China es uno de los mayores sistemas acuíferos del mundo y soporta una enorme explotación de su agua subterránea, las cuales han originado grandes

  13. The exosome complex establishes a barricade to erythroid maturation.

    PubMed

    McIver, Skye C; Kang, Yoon-A; DeVilbiss, Andrew W; O'Driscoll, Chelsea A; Ouellette, Jonathan N; Pope, Nathaniel J; Camprecios, Genis; Chang, Chan-Jung; Yang, David; Bouhassira, Eric E; Ghaffari, Saghi; Bresnick, Emery H

    2014-10-01

    Complex genetic networks control hematopoietic stem cell differentiation into progenitors that give rise to billions of erythrocytes daily. Previously, we described a role for the master regulator of erythropoiesis, GATA-1, in inducing genes encoding components of the autophagy machinery. In this context, the Forkhead transcription factor, Foxo3, amplified GATA-1-mediated transcriptional activation. To determine the scope of the GATA-1/Foxo3 cooperativity, and to develop functional insights, we analyzed the GATA-1/Foxo3-dependent transcriptome in erythroid cells. GATA-1/Foxo3 repressed expression of Exosc8, a pivotal component of the exosome complex, which mediates RNA surveillance and epigenetic regulation. Strikingly, downregulating Exosc8, or additional exosome complex components, in primary erythroid precursor cells induced erythroid cell maturation. Our results demonstrate a new mode of controlling erythropoiesis in which multiple components of the exosome complex are endogenous suppressors of the erythroid developmental program. PMID:25115889

  14. The exosome complex establishes a barricade to erythroid maturation

    PubMed Central

    McIver, Skye C.; Kang, Yoon-A; DeVilbiss, Andrew W.; O’Driscoll, Chelsea A.; Ouellette, Jonathan N.; Pope, Nathaniel J.; Camprecios, Genis; Chang, Chan-Jung; Yang, David; Bouhassira, Eric E.; Ghaffari, Saghi

    2014-01-01

    Complex genetic networks control hematopoietic stem cell differentiation into progenitors that give rise to billions of erythrocytes daily. Previously, we described a role for the master regulator of erythropoiesis, GATA-1, in inducing genes encoding components of the autophagy machinery. In this context, the Forkhead transcription factor, Foxo3, amplified GATA-1–mediated transcriptional activation. To determine the scope of the GATA-1/Foxo3 cooperativity, and to develop functional insights, we analyzed the GATA-1/Foxo3-dependent transcriptome in erythroid cells. GATA-1/Foxo3 repressed expression of Exosc8, a pivotal component of the exosome complex, which mediates RNA surveillance and epigenetic regulation. Strikingly, downregulating Exosc8, or additional exosome complex components, in primary erythroid precursor cells induced erythroid cell maturation. Our results demonstrate a new mode of controlling erythropoiesis in which multiple components of the exosome complex are endogenous suppressors of the erythroid developmental program. PMID:25115889

  15. Implementing the UN Decade of Education for Sustainable Development (DESD): achievements, open questions and strategies for the way forward

    NASA Astrophysics Data System (ADS)

    Pigozzi, Mary Joy

    2010-06-01

    This paper looks at the implementation of the DESD from a global perspective. It takes the position that quality education is fundamental for learning how to live sustainably, and that the DESD needs to be better positioned in the education landscape and conceived as a global social movement that must be fostered and nurtured for the well-being of humankind. It suggests that, while there has been progress, much remains to be achieved. Several key challenges are identified. With regard to overcoming these obstacles, it focuses on macro-level strategies that would allow the development of environments in which actions can take root and grow so that the work of the DESD endures beyond the decade itself. Finally, it suggests that there are some opportunities that can be seized to make the task ahead easier to accomplish.

  16. Population Pharmacokinetics of Colistin Methanesulfonate in Rats: Achieving Sustained Lung Concentrations of Colistin for Targeting Respiratory Infections

    PubMed Central

    W. S. Yapa, Shalini; Li, Jian; Porter, Christopher J. H.; Nation, Roger L.

    2013-01-01

    Colistin methanesulfonate (CMS), the inactive prodrug of colistin, is administered by inhalation for the management of respiratory infections. However, limited pharmacokinetic data are available for CMS and colistin following pulmonary delivery. This study investigates the pharmacokinetics of CMS and colistin following intravenous (i.v.) and intratracheal (i.t.) administration in rats and determines the targeting advantage after direct delivery into the lungs. In addition to plasma, bronchoalveolar lavage (BAL) fluid was collected to quantify drug concentrations in lung epithelial lining fluid (ELF). The resulting data were analyzed using a population modeling approach in S-ADAPT. A three-compartment model described the disposition of both compounds in plasma following i.v. administration. The estimated mean clearance from the central compartment was 0.122 liters/h for CMS and 0.0657 liters/h for colistin. Conversion of CMS to colistin from all three compartments was required to fit the plasma data. The fraction of the i.v. dose converted to colistin in the systemic circulation was 0.0255. Two BAL fluid compartments were required to reflect drug kinetics in the ELF after i.t. dosing. A slow conversion of CMS (mean conversion time [MCTCMS] = 3.48 h) in the lungs contributed to high and sustained concentrations of colistin in ELF. The fraction of the CMS dose converted to colistin in ELF (fm,ELF = 0.226) was higher than the corresponding fractional conversion in plasma after i.v. administration. In conclusion, pulmonary administration of CMS achieves high and sustained exposures of colistin in lungs for targeting respiratory infections. PMID:23917323

  17. MEIS1 regulates early erythroid and megakaryocytic cell fate

    PubMed Central

    Zeddies, Sabrina; Jansen, Sjoert B. G.; di Summa, Franca; Geerts, Dirk; Zwaginga, Jaap J.; van der Schoot, C. Ellen; von Lindern, Marieke; Thijssen-Timmer, Daphne C.

    2014-01-01

    MEIS1 is a transcription factor expressed in hematopoietic stem and progenitor cells and in mature megakaryocytes. This biphasic expression of MEIS1 suggests that the function of MEIS1 in stem cells is distinct from its function in lineage committed cells. Mouse models show that Meis1 is required for renewal of stem cells, but the function of MEIS1 in human hematopoietic progenitor cells has not been investigated. We show that two MEIS1 splice variants are expressed in hematopoietic progenitor cells. Constitutive expression of both variants directed human hematopoietic progenitors towards a megakaryocyte-erythrocyte progenitor fate. Ectopic expression of either MEIS1 splice variant in common myeloid progenitor cells, and even in granulocyte-monocyte progenitors, resulted in increased erythroid differentiation at the expense of granulocyte and macrophage differentiation. Conversely, silencing MEIS1 expression in progenitor cells induced a block in erythroid expansion and decreased megakaryocytic colony formation capacity. Gene expression profiling revealed that both MEIS1 splice variants induce a transcriptional program enriched for erythroid and megakaryocytic genes. Our results indicate that MEIS1 expression induces lineage commitment towards a megakaryocyte-erythroid progenitor cell fate in common myeloid progenitor cells through activation of genes that define a megakaryocyte-erythroid-specific gene expression program. PMID:25107888

  18. Altered chromatin occupancy of master regulators underlies evolutionary divergence in the transcriptional landscape of erythroid differentiation.

    PubMed

    Ulirsch, Jacob C; Lacy, Jessica N; An, Xiuli; Mohandas, Narla; Mikkelsen, Tarjei S; Sankaran, Vijay G

    2014-12-01

    Erythropoiesis is one of the best understood examples of cellular differentiation. Morphologically, erythroid differentiation proceeds in a nearly identical fashion between humans and mice, but recent evidence has shown that networks of gene expression governing this process are divergent between species. We undertook a systematic comparative analysis of six histone modifications and four transcriptional master regulators in primary proerythroblasts and erythroid cell lines to better understand the underlying basis of these transcriptional differences. Our analyses suggest that while chromatin structure across orthologous promoters is strongly conserved, subtle differences are associated with transcriptional divergence between species. Many transcription factor (TF) occupancy sites were poorly conserved across species (∼25% for GATA1, TAL1, and NFE2) but were more conserved between proerythroblasts and cell lines derived from the same species. We found that certain cis-regulatory modules co-occupied by GATA1, TAL1, and KLF1 are under strict evolutionary constraint and localize to genes necessary for erythroid cell identity. More generally, we show that conserved TF occupancy sites are indicative of active regulatory regions and strong gene expression that is sustained during maturation. Our results suggest that evolutionary turnover of TF binding sites associates with changes in the underlying chromatin structure, driving transcriptional divergence. We provide examples of how this framework can be applied to understand epigenomic variation in specific regulatory regions, such as the β-globin gene locus. Our findings have important implications for understanding epigenomic changes that mediate variation in cellular differentiation across species, while also providing a valuable resource for studies of hematopoiesis. PMID:25521328

  19. Altered Chromatin Occupancy of Master Regulators Underlies Evolutionary Divergence in the Transcriptional Landscape of Erythroid Differentiation

    PubMed Central

    Ulirsch, Jacob C.; Lacy, Jessica N.; An, Xiuli; Mohandas, Narla; Mikkelsen, Tarjei S.; Sankaran, Vijay G.

    2014-01-01

    Erythropoiesis is one of the best understood examples of cellular differentiation. Morphologically, erythroid differentiation proceeds in a nearly identical fashion between humans and mice, but recent evidence has shown that networks of gene expression governing this process are divergent between species. We undertook a systematic comparative analysis of six histone modifications and four transcriptional master regulators in primary proerythroblasts and erythroid cell lines to better understand the underlying basis of these transcriptional differences. Our analyses suggest that while chromatin structure across orthologous promoters is strongly conserved, subtle differences are associated with transcriptional divergence between species. Many transcription factor (TF) occupancy sites were poorly conserved across species (∼25% for GATA1, TAL1, and NFE2) but were more conserved between proerythroblasts and cell lines derived from the same species. We found that certain cis-regulatory modules co-occupied by GATA1, TAL1, and KLF1 are under strict evolutionary constraint and localize to genes necessary for erythroid cell identity. More generally, we show that conserved TF occupancy sites are indicative of active regulatory regions and strong gene expression that is sustained during maturation. Our results suggest that evolutionary turnover of TF binding sites associates with changes in the underlying chromatin structure, driving transcriptional divergence. We provide examples of how this framework can be applied to understand epigenomic variation in specific regulatory regions, such as the β-globin gene locus. Our findings have important implications for understanding epigenomic changes that mediate variation in cellular differentiation across species, while also providing a valuable resource for studies of hematopoiesis. PMID:25521328

  20. Biology of Heme in Mammalian Erythroid Cells and Related Disorders

    PubMed Central

    Fujiwara, Tohru; Harigae, Hideo

    2015-01-01

    Heme is a prosthetic group comprising ferrous iron (Fe2+) and protoporphyrin IX and is an essential cofactor in various biological processes such as oxygen transport (hemoglobin) and storage (myoglobin) and electron transfer (respiratory cytochromes) in addition to its role as a structural component of hemoproteins. Heme biosynthesis is induced during erythroid differentiation and is coordinated with the expression of genes involved in globin formation and iron acquisition/transport. However, erythroid and nonerythroid cells exhibit distinct differences in the heme biosynthetic pathway regulation. Defects of heme biosynthesis in developing erythroblasts can have profound medical implications, as represented by sideroblastic anemia. This review will focus on the biology of heme in mammalian erythroid cells, including the heme biosynthetic pathway as well as the regulatory role of heme and human disorders that arise from defective heme synthesis. PMID:26557657

  1. Erythroid differentiation is augmented in Reelin-deficient K562 cells and homozygous reeler mice.

    PubMed

    Chu, Hui-Chun; Lee, Hsing-Ying; Huang, Yen-Shu; Tseng, Wei-Lien; Yen, Ching-Ju; Cheng, Ju-Chien; Tseng, Ching-Ping

    2014-01-01

    Reelin is an extracellular glycoprotein that is highly conserved in mammals. In addition to its expression in the nervous system, Reelin is present in erythroid cells but its function there is unknown. We report in this study that Reelin is up-regulated during erythroid differentiation of human erythroleukemic K562 cells and is expressed in the erythroid progenitors of murine bone marrow. Reelin deficiency promotes erythroid differentiation of K562 cells and augments erythroid production in murine bone marrow. In accordance with these findings, Reelin deficiency attenuates AKT phosphorylation of the Ter119(+)CD71(+) erythroid progenitors and alters the cell number and frequency of the progenitors at different erythroid differentiation stages. A regulatory role of Reelin in erythroid differentiation is thus defined. PMID:24239537

  2. Sustain

    SciTech Connect

    2013-08-20

    Current building energy simulation technology requires excessive labor, time and expertise to create building energy models, excessive computational time for accurate simulations and difficulties with the interpretation of the results. These deficiencies can be ameliorated using modern graphical user interfaces and algorithms which take advantage of modern computer architectures and display capabilities. To prove this hypothesis, we developed an experimental test bed for building energy simulation. This novel test bed environment offers an easy-to-use interactive graphical interface, provides access to innovative simulation modules that run at accelerated computational speeds, and presents new graphics visualization methods to interpret simulation results. Our system offers the promise of dramatic ease of use in comparison with currently available building energy simulation tools. Its modular structure makes it suitable for early stage building design, as a research platform for the investigation of new simulation methods, and as a tool for teaching concepts of sustainable design. Improvements in the accuracy and execution speed of many of the simulation modules are based on the modification of advanced computer graphics rendering algorithms. Significant performance improvements are demonstrated in several computationally expensive energy simulation modules. The incorporation of these modern graphical techniques should advance the state of the art in the domain of whole building energy analysis and building performance simulation, particularly at the conceptual design stage when decisions have the greatest impact. More importantly, these better simulation tools will enable the transition from prescriptive to performative energy codes, resulting in better, more efficient designs for our future built environment.

  3. Sustain

    Energy Science and Technology Software Center (ESTSC)

    2013-08-20

    Current building energy simulation technology requires excessive labor, time and expertise to create building energy models, excessive computational time for accurate simulations and difficulties with the interpretation of the results. These deficiencies can be ameliorated using modern graphical user interfaces and algorithms which take advantage of modern computer architectures and display capabilities. To prove this hypothesis, we developed an experimental test bed for building energy simulation. This novel test bed environment offers an easy-to-use interactivemore » graphical interface, provides access to innovative simulation modules that run at accelerated computational speeds, and presents new graphics visualization methods to interpret simulation results. Our system offers the promise of dramatic ease of use in comparison with currently available building energy simulation tools. Its modular structure makes it suitable for early stage building design, as a research platform for the investigation of new simulation methods, and as a tool for teaching concepts of sustainable design. Improvements in the accuracy and execution speed of many of the simulation modules are based on the modification of advanced computer graphics rendering algorithms. Significant performance improvements are demonstrated in several computationally expensive energy simulation modules. The incorporation of these modern graphical techniques should advance the state of the art in the domain of whole building energy analysis and building performance simulation, particularly at the conceptual design stage when decisions have the greatest impact. More importantly, these better simulation tools will enable the transition from prescriptive to performative energy codes, resulting in better, more efficient designs for our future built environment.« less

  4. The heme exporter Flvcr1 regulates expansion and differentiation of committed erythroid progenitors by controlling intracellular heme accumulation.

    PubMed

    Mercurio, Sonia; Petrillo, Sara; Chiabrando, Deborah; Bassi, Zuni Irma; Gays, Dafne; Camporeale, Annalisa; Vacaru, Andrei; Miniscalco, Barbara; Valperga, Giulio; Silengo, Lorenzo; Altruda, Fiorella; Baron, Margaret H; Santoro, Massimo Mattia; Tolosano, Emanuela

    2015-06-01

    Feline leukemia virus subgroup C receptor 1 (Flvcr1) encodes two heme exporters: FLVCR1a, which localizes to the plasma membrane, and FLVCR1b, which localizes to mitochondria. Here, we investigated the role of the two Flvcr1 isoforms during erythropoiesis. We showed that, in mice and zebrafish, Flvcr1a is required for the expansion of committed erythroid progenitors but cannot drive their terminal differentiation, while Flvcr1b contributes to the expansion phase and is required for differentiation. FLVCR1a-down-regulated K562 cells have defective proliferation, enhanced differentiation, and heme loading in the cytosol, while FLVCR1a/1b-deficient K562 cells show impairment in both proliferation and differentiation, and accumulate heme in mitochondria. These data support a model in which the coordinated expression of Flvcr1a and Flvcr1b contributes to control the size of the cytosolic heme pool required to sustain metabolic activity during the expansion of erythroid progenitors and to allow hemoglobinization during their terminal maturation. Consistently, reduction or increase of the cytosolic heme rescued the erythroid defects in zebrafish deficient in Flvcr1a or Flvcr1b, respectively. Thus, heme export represents a tightly regulated process that controls erythropoiesis. PMID:25795718

  5. Proliferation and maturation of human erythroid progenitors in liquid culture.

    PubMed

    Fibach, E; Manor, D; Oppenheim, A; Rachmilewitz, E A

    1989-01-01

    Hemopoiesis is studied in vitro mainly in semisolid culture, where hemopoietic progenitors develop into discrete colonies. We describe a liquid culture system that supports the proliferation and maturation of human erythroid progenitors. We seeded mononuclear cells from the peripheral blood (PB) of patients with beta-thalassemia in liquid medium in the presence of conditioned medium from human bladder carcinoma cells. Seven days later, RBCs, normoblasts, granulocytes, and monocytes disappeared, and the number of lymphocytes dropped considerably. In contrast, erythroid colony-forming cells increased fourfold to tenfold. The next step entailed the removal of colony-stimulating factor (CSF) and CSF-secreting cells, the exclusion of macrophages by harvesting nonadherent cells, and the lysis of T lymphocytes by treatment with monoclonal rat antihuman lymphocyte antibodies (CAMPATH-1) and complement. Reculture of the remaining cells in liquid medium supplemented with recombinant erythropoietin (EPO) resulted in the exclusive development of erythroid cells, with myeloid cells reduced to less than 2%. Stainable hemoglobin (Hb) appeared on day 3, with over 85% of the population containing hemoglobin by day 11 and the cell number increasing from 0.2 X 10(6) to 3 X 10(6) mL. By permitting the manipulation of culture conditions and components and increasing the cell yield, the liquid system may facilitate quantitative analysis of growth kinetics as well as biochemical and immunologic characterization of the developing erythroid cell. PMID:2910352

  6. Acute myeloid leukaemia (M6B: pure acute erythroid leukaemia) in a Thoroughbred foal.

    PubMed

    Forbes, G; Feary, D J; Savage, C J; Nath, L; Church, S; Lording, P

    2011-07-01

    A 10-week-old Thoroughbred filly was referred for anaemia of 4 weeks' duration. Haematology revealed severe anaemia and panleucopenia. Cytological examination of bone marrow smears revealed a myeloid to erythroid ratio <0.02:1 (reference range 0.5-2.4:1.0) and an abundance of erythroid precursor cells. The erythroid cell population included rubriblasts, prorubricytes and rubricytes, with only scant numbers of metarubricytes present. There were numerous mitotic erythroid cells, some of which were atypical and megaloblastic. These cytomorphological changes are consistent with pure acute erythroid leukaemia. No treatment was instituted and the filly died three days after presentation. This case illustrates the need to consider both haematology and bone marrow findings to establish a diagnosis of pure erythroid leukaemia. To our knowledge, there is no documented case of acute myeloproliferative disease in horses involving cells of erythroid lineage, but this condition should be considered a differential diagnosis for horses presenting with anaemia. PMID:21696377

  7. The role of DNA methylation in catechol-enhanced erythroid differentiation of K562 cells

    SciTech Connect

    Li, Xiao-Fei; Wu, Xiao-Rong; Xue, Ming; Wang, Yan; Wang, Jie; Li, Yang; Suriguga,; Zhang, Guang-Yao; Yi, Zong-Chun

    2012-11-15

    Catechol is one of phenolic metabolites of benzene in vivo. Catechol is also widely used in pharmaceutical and chemical industries. In addition, fruits, vegetables and cigarette smoke also contain catechol. Our precious study showed that several benzene metabolites (phenol, hydroquinone, and 1,2,4-benzenetriol) inhibited erythroid differentiation of K562 cells. In present study, the effect of catechol on erythroid differentiation of K562 cells was investigated. Moreover, to address the role of DNA methylation in catechol-induced effect on erythroid differentiation in K562 cells, methylation levels of erythroid-specific genes were analyzed by Quantitative MassARRAY methylation analysis platform. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation in K562 cells in concentration- and time-dependent manners. The mRNA expression of erythroid specific genes, including α-globin, β-globin, γ-globin, erythroid 5-aminolevulinate synthase, erythroid porphobilinogen deaminase, and transcription factor GATA-1 genes, showed a significant concentration-dependent increase in catechol-treated K562 cells. The exposure to catechol caused a decrease in DNA methylation levels at a few CpG sites in some erythroid specific genes including α-globin, β-globin and erythroid porphobilinogen deaminase genes. These results indicated that catechol improved erythroid differentiation potency of K562 cells at least partly via up-regulating transcription of some erythroid related genes, and suggested that inhibition of DNA methylation might be involved in up-regulated expression of some erythroid related genes. -- Highlights: ► Catechol enhanced hemin-induced hemoglobin accumulation. ► Exposure to catechol resulted in up-regulated expression of erythroid genes. ► Catechol reduced methylation levels at some CpG sites in erythroid genes.

  8. Radioactive Waste Management - It's Role in contributing and achieving Sustainability. R1.13 The French strategy of waste management: technical and political dimensions of sustainability

    SciTech Connect

    Bazile, F.

    2007-07-01

    The sustainability of an energy policy depends on the manner in which it satisfies environmental, economical and social requirements. Nuclear energy is not an exception. The objectives of the future nuclear systems, as defined in the Generation IV International Forum, tend to optimize the ability of nuclear energy to satisfy sustainable development goals. In this regard, they involve strong commitments concerning waste management policy : five designs in six are based on a closed fuel cycle, in order to minimize the volume and radiotoxicity of final waste, and to recycle the fissile materials to save natural resources. Since its beginnings, the French civil nuclear programme has considered a long-term perspective and has developed spent fuel reprocessing. The French current industrial technology has already permitted to recycle 96% of spent fuel materials, to save 30% of natural resources, to reduce by 5 the amount of waste and to reduce by 10 the waste radiotoxicity, all these benefits for less than 6% of the kWh total cost. This strategy has always been criticized by the nuclear opponents, precisely because they saw that it was a sustainable way, and didn't accept to consider nuclear energy as a sustainable source of power. Two arguments were put forward these criticisms. First, the cost of reprocessing versus once-through cycle and second, the risk of proliferation induced by U-Pu partitioning process. These arguments were also invoked in international debates, and they have also been pleaded by the anti-nukes during the National Debate on HLLLW, at the end of 2005, preceding the vote of a new law in 2006 by the French parliament. Fortunately they have not convinced public opinion in France nor political decision-makers. A majority of people with no regard to technical background understand that recycling and saving the natural resources are sustainable principles. And, from a technical point of view, the 6% over cost does not seem significant considering the

  9. Enhanced inhibition of parvovirus B19 replication by cidofovir in extendedly exposed erythroid progenitor cells.

    PubMed

    Bonvicini, Francesca; Bua, Gloria; Manaresi, Elisabetta; Gallinella, Giorgio

    2016-07-15

    Human parvovirus B19 (B19V) commonly induces self-limiting infections but can also cause severe clinical manifestations in patients with underlying haematological disorders or with immune system deficits. Currently, therapeutic options for B19V entirely rely on symptomatic and supportive treatments since a specific antiviral therapy is not yet available. Recently a first step in the research for active compounds inhibiting B19V replication has allowed identifying the acyclic nucleoside phosphonate cidofovir (CDV). Herein, the effect of CDV against B19V replication was characterized in human erythroid progenitor cells (EPCs) cultured and infected following different experimental approaches to replicate in vitro the infection of an expanding erythroid cell population in the bone marrow. B19V replication was selectively inhibited both in infected EPCs extendedly exposed to CDV 500μM (viral inhibition 82%) and in serially infected EPCs cultures with passage of the virus progeny, constantly under drug exposure (viral inhibition 99%). In addition, a potent inhibitory effect against B19V (viral inhibition 92%) was assessed in a short-term infection of EPCs treated with CDV 500μM 1day before viral infection. In the evaluated experimental conditions, the enhanced effect of CDV against B19V might be ascribed both to the increased intracellular drug concentration achieved by extended exposure, and to a progressive reduction in efficiency of the replicative process within treated EPCs population. PMID:27071853

  10. Going Green: A Comparative Case Study of How Three Higher Education Institutions Achieved Progressive Measures of Environmental Sustainability

    ERIC Educational Resources Information Center

    James, Matthew R.

    2009-01-01

    Leal Filho, MacDermot, and Padgam (1996) contended that post-secondary institutions are well suited to take on leadership responsibilities for society's environmental protection. Higher education has the unique academic freedom to engage in critical thinking and bold experimentation in environmental sustainability (Cortese, 2003). Although…

  11. When wastewater has worth: Water reconditioning opportunities in the food industry to achieve sustainable food manufacturing (abstract)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major sustainability goal of food processing wastewater (FPWW) management is to not only decrease environmental pollution but also utilize valuable co-products present in the FPWW. Many processed food products, especially those from fruits and vegetables, result in FPWW streams that contain compou...

  12. Institutional Incorporation of Screening, Brief Intervention, and Referral to Treatment (SBIRT) in Residency Training: Achieving a Sustainable Curriculum

    ERIC Educational Resources Information Center

    Scott, Denise M.; McLaurin-Jones, TyWanda; Brown, Fannie D.; Newton, Robin; Marshall, Vanessa J.; Kalu, Nnenna; Cain, Gloria E.; Taylor, Robert E.

    2012-01-01

    The success of implementing a screening, brief intervention and referral to treatment (SBIRT) program within a medical residency program for sustainability is contingent upon a well-crafted training curriculum that incorporates substance abuse education and clinical practice skills. The goal of the Howard University (HU) SBIRT program is to train…

  13. Survival and proliferative roles of erythropoietin beyond the erythroid lineage

    PubMed Central

    Noguchi, Constance Tom; Wang, Li; Rogers, Heather M.; Teng, Ruifeng; Jia, Yi

    2011-01-01

    Since the isolation and purification of erythropoietin (EPO) in 1977, the essential role of EPO for mature red blood cell production has been well established. The cloning and production of recombinant human EPO led to its widespread use in treating patients with anaemia. However, the biological activity of EPO is not restricted to regulation of erythropoiesis. EPO receptor (EPOR) expression is also found in endothelial, brain, cardiovascular and other tissues, although at levels considerably lower than that of erythroid progenitor cells. This review discusses the survival and proliferative activity of EPO that extends beyond erythroid progenitor cells. Loss of EpoR expression in mouse models provides evidence for the role of endogenous EPO signalling in nonhaematopoietic tissue during development or for tissue maintenance and/or repair. Determining the extent and distribution of receptor expression provides insights into the potential protective activity of erythropoietin in brain, heart and other nonhaematopoietic tissues. PMID:19040789

  14. The effect of iron overload and chelation on erythroid differentiation.

    PubMed

    Taoka, Kazuki; Kumano, Keiki; Nakamura, Fumihiko; Hosoi, Masataka; Goyama, Susumu; Imai, Yoichi; Hangaishi, Akira; Kurokawa, Mineo

    2012-02-01

    We investigated the mechanisms of hematopoietic disorders caused by iron overload and chelation, in particular, the inhibition of erythroblast differentiation. Murine c-kit(+) progenitor cells or human CD34(+) peripheral blood hematopoietic progenitors were differentiated in vitro to the erythroid lineage with free iron and/or an iron chelator. Under iron overload, formation of erythroid burst-forming unit colonies and differentiation to mature erythroblasts were significantly suppressed; these effects were canceled by iron chelation with deferoxamine (DFO). Moreover, excessive iron burden promoted apoptosis in immature erythroblasts by elevating intracellular reactive oxygen species (ROS). Interestingly, both DFO and a potent anti-oxidant agent reduced intracellular ROS levels and suppressed apoptosis, thus restoring differentiation to mature erythroblasts. Accordingly, intracellular ROS may represent a new therapeutic target in the treatment of iron overload. PMID:22193844

  15. Cpeb4-mediated translational regulatory circuitry controls terminal erythroid differentiation.

    PubMed

    Hu, Wenqian; Yuan, Bingbing; Lodish, Harvey F

    2014-09-29

    While we have considerable understanding of the transcriptional networks controlling mammalian cell differentiation, our knowledge of posttranscriptional regulatory events is very limited. Using differentiation of primary erythroid cells as a model, we show that the sequence-specific mRNA-binding protein Cpeb4 is strongly induced by the erythroid-important transcription factors Gata1 and Tal1 and is essential for terminal erythropoiesis. By interacting with the translation initiation factor eIF3, Cpeb4 represses the translation of a large set of mRNAs, including its own mRNA. Thus, transcriptional induction and translational repression combine to form a negative feedback loop to control Cpeb4 protein levels within a specific range that is required for terminal erythropoiesis. Our study provides an example of how translational control is integrated with transcriptional regulation to precisely control gene expression during mammalian cell differentiation. PMID:25220394

  16. Haemoglobin biosynthesis site in rabbit embryo erythroid cells.

    PubMed

    Cianciarullo, Aurora M; Bertho, Alvaro L; Soares, Maurilio J; Hosoda, Tânia M; Nogueira-Silva, Simone; Beçak, Willy

    2003-01-01

    Properly metabolized globin synthesis and iron uptake are indispensable for erythroid cell differentiation and maturation. Mitochondrial participation is crucial in the process of haeme synthesis for cytochromes and haemoglobin. We studied the final biosynthesis site of haemoglobin using an ultrastructural approach, with erythroid cells obtained from rabbit embryos, in order to compare these results with those of animals treated with saponine or phenylhydrazine. Our results are similar to those obtained in assays with adult mammals, birds, amphibians, reptiles and fish, after induction of haemolytic anaemia. Therefore, the treatment did not interfere with the process studied, confirming our previous findings. Immunoelectron microscopy showed no labelling of mitochondria or other cellular organelles supposedly involved in the final biosynthesis of haemoglobin molecules, suggesting instead that it occurs free in the cytoplasm immediately after the liberation of haeme from the mitochondria, by electrostatic attraction between haeme and globin chains. PMID:12972280

  17. In vitro apoptotic cell death during erythroid differentiation.

    PubMed

    Zamai, L; Burattini, S; Luchetti, F; Canonico, B; Ferri, P; Melloni, E; Gonelli, A; Guidotti, L; Papa, S; Falcieri, E

    2004-03-01

    Erythropoiesis occurs in bone marrow and it has been shown that during in vivo erythroid differentiation some immature erythroblasts undergo apoptosis. In this regard, it is known that immature erythroblasts are FasL- and TRAIL-sensitive and can be killed by cells expressing these ligand molecules. In the present study, we have investigated the cell death phenomenon that occurs during a common unilineage model of erythroid development. Purified CD34+ human haemopoietic progenitors were cultured in vitro in the presence of SCF, IL-3 and erythropoietin. Their differentiation stages and apoptosis were followed by multiple technical approaches. Flow cytometric evaluation of surface and intracellular molecules revealed that glycophorin A appeared at day 3-4 of incubation and about 75% of viable cells co-expressed high density glycophorin A (Gly(bright)) and adult haemoglobin at day 14 of culture, indicating that this system reasonably recapitulates in vivo normal erythropoiesis. Interestingly, when mature (Gly(bright)) erythroid cells reached their higher percentages (day 14) almost half of cultured cells were apoptotic. Morphological studies indicated that the majority of dead cells contained cytoplasmic granular material typical of basophilic stage, and DNA analysis by flow cytometry and TUNEL reaction revealed nuclear fragmentation. These observations indicate that in vitro unilineage erythroid differentiation, as in vivo, is associated with apoptotic cell death of cells with characteristics of basophilic erythroblasts. We suggest that the interactions between different death receptors on immature basophilic erythroblasts with their ligands on more mature erythroblasts may contribute to induce apoptosis in vitro. PMID:15004520

  18. The Effects of Sustained Classroom-Embedded Teacher Professional Learning on Teacher Efficacy and Related Student Achievement

    ERIC Educational Resources Information Center

    Bruce, Catherine D.; Esmonde, Indigo; Ross, John; Dookie, Lesley; Beatty, Ruth

    2010-01-01

    This paper reports on the impact of a classroom-embedded professional learning (PL) program for mathematics teaching in two contrasting districts in Canada, and investigates the relationship between teacher efficacy and student achievement. Before the PL, District A had lower teacher efficacy and student achievement than District B, but after the…

  19. Global transcriptome analyses of human and murine terminal erythroid differentiation

    PubMed Central

    An, Xiuli; Schulz, Vincent P.; Li, Jie; Wu, Kunlu; Liu, Jing; Xue, Fumin; Hu, Jingping; Mohandas, Narla

    2014-01-01

    We recently developed fluorescence-activated cell sorting (FACS)-based methods to purify morphologically and functionally discrete populations of cells, each representing specific stages of terminal erythroid differentiation. We used these techniques to obtain pure populations of both human and murine erythroblasts at distinct developmental stages. RNA was prepared from these cells and subjected to RNA sequencing analyses, creating unbiased, stage-specific transcriptomes. Tight clustering of transcriptomes from differing stages, even between biologically different replicates, validated the utility of the FACS-based assays. Bioinformatic analyses revealed that there were marked differences between differentiation stages, with both shared and dissimilar gene expression profiles defining each stage within transcriptional space. There were vast temporal changes in gene expression across the differentiation stages, with each stage exhibiting unique transcriptomes. Clustering and network analyses revealed that varying stage-specific patterns of expression observed across differentiation were enriched for genes of differing function. Numerous differences were present between human and murine transcriptomes, with significant variation in the global patterns of gene expression. These data provide a significant resource for studies of normal and perturbed erythropoiesis, allowing a deeper understanding of mechanisms of erythroid development in various inherited and acquired erythroid disorders. PMID:24637361

  20. Identification of human erythroid lineage-committed progenitors.

    PubMed

    Mori, Yasuo; Akashi, Koichi; Weissman, Irving L

    2016-05-01

    Elucidating the developmental pathway leading to erythrocytes and being able to isolate their progenitors is crucial to understanding and treating disorders of red cell imbalance such as anemia, myelodysplastic syndrome, and polycythemia vera. Endoglin (CD105) is a key marker for purifying mouse erythroid lineage-committed progenitors (EPs) from bone marrow. Herein, we show that human EPs can also be isolated from adult bone marrow. We identified three subfractions that possessed different expression patterns of CD105 and CD71 within the previously defined human megakaryocyte/erythrocyte progenitor (hMEP; Lineage-CD34(+)CD38(+)IL-3Rα(-)CD45RA(-)) population. Both CD71(-)CD105(-) and CD71(+)CD105(-) MEPs, at least in vitro, retained bipotency for the megakaryocyte (MegK) and erythrocyte (E) lineages, although the latter sub-population had a differentiation potential skewed toward the E-lineage. Notably, the differentiation output of the CD71(+)CD105(+) subset of cells within the MEP population was completely restricted to the E-lineage with the loss of MegK potential; thus, we termed CD71(+)CD105(-) MEPs and CD71(+)CD105(+) cells as E-biased MEPs (E-MEPs) and EPs, respectively. These previously unclassified populations may facilitate understanding of the molecular mechanisms governing human erythroid development and serve as potential therapeutic targets in disorders of the erythroid lineage. PMID:27263782

  1. Lipid changes associated with erythroid differentiation of Friend erythroleukemia cells.

    PubMed

    Fallani, A; Arcangeli, A; Ruggieri, S

    1987-01-01

    Friend erythroleukemia cells were induced to differentiate by dimethyl sulfoxide (DMSO) and hexamethylene-bis-acetamide (HBMA) in order to investigate whether their lipid characteristics, common to other systems of transformed cells, revert to a normal differentiation pattern. DBA/2 mouse erythrocytes were examined as a model of terminal differentiation in erythroid lineage. Variants of erythroleukemia cells not inducible to erythroid differentiation by DMSO and HMBA were also used in this study, in order to test whether lipid modifications occurring in differentiated erythroleukemia cells were related to the differentiation process or caused by specific effects of the inducers. Friend erythroleukemia cells showed the same lipid characteristics as those found in other transformed cell types. That is, a high level of ether-linked lipids and low percentages of long chain polyunsaturated fatty acids along with an accumulation of monoenoic fatty acids in phospholipids. These lipid characteristics remained unchanged when erythroleukemia cells were induced to differentiation by either DMSO or HMBA. However, other lipid components of erythroleukemia cells, e.g., phosphatidylethanolamine and triglycerides, were affected by erythroid differentiation. There were also changes of some lipid components of erythroleukemia cells, such as cholesteryl esters, which were related to specific effects of the inducers. Both DMSO- and HMBA-resistant variants differed from the inducible erythroleukemia cells, mainly in their ether-linked phospholipid pattern. PMID:3475757

  2. Sustainable energy for all. Technical report of task force 1 in support of the objective to achieve universal access to modern energy services by 2030

    SciTech Connect

    Birol, Fatih

    2012-04-15

    The UN Secretary General established the Sustainable Energy for All initiative in order to guide and support efforts to achieve universal access to modern energy, rapidly increase energy efficiency, and expand the use of renewable energies. Task forces were formed involving prominent energy leaders and experts from business, government, academia and civil society worldwide. The goal of the Task Forces is to inform the implementation of the initiative by identifying challenges and opportunities for achieving its objectives. This report contains the findings of Task Force One which is dedicated to the objective of achieving universal access to modern energy services by 2030. The report shows that universal energy access can be realized by 2030 with strong, focused actions set within a coordinated framework.

  3. Characterization of the transcriptome profiles related to globin gene switching during in vitro erythroid maturation

    PubMed Central

    2012-01-01

    Background The fetal and adult globin genes in the human β-globin cluster on chromosome 11 are sequentially expressed to achieve normal hemoglobin switching during human development. The pharmacological induction of fetal γ-globin (HBG) to replace abnormal adult sickle βS-globin is a successful strategy to treat sickle cell disease; however the molecular mechanism of γ-gene silencing after birth is not fully understood. Therefore, we performed global gene expression profiling using primary erythroid progenitors grown from human peripheral blood mononuclear cells to characterize gene expression patterns during the γ-globin to β-globin (γ/β) switch observed throughout in vitro erythroid differentiation. Results We confirmed erythroid maturation in our culture system using cell morphologic features defined by Giemsa staining and the γ/β-globin switch by reverse transcription-quantitative PCR (RT-qPCR) analysis. We observed maximal γ-globin expression at day 7 with a switch to a predominance of β-globin expression by day 28 and the γ/β-globin switch occurred around day 21. Expression patterns for transcription factors including GATA1, GATA2, KLF1 and NFE2 confirmed our system produced the expected pattern of expression based on the known function of these factors in globin gene regulation. Subsequent gene expression profiling was performed with RNA isolated from progenitors harvested at day 7, 14, 21, and 28 in culture. Three major gene profiles were generated by Principal Component Analysis (PCA). For profile-1 genes, where expression decreased from day 7 to day 28, we identified 2,102 genes down-regulated > 1.5-fold. Ingenuity pathway analysis (IPA) for profile-1 genes demonstrated involvement of the Cdc42, phospholipase C, NF-Kβ, Interleukin-4, and p38 mitogen activated protein kinase (MAPK) signaling pathways. Transcription factors known to be involved in γ-and β-globin regulation were identified. The same approach was used to generate profile-2

  4. Erythroid-Specific Expression of LIN28A Is Sufficient for Robust Gamma-Globin Gene and Protein Expression in Adult Erythroblasts

    PubMed Central

    Byrnes, Colleen; Kaushal, Megha; Rabel, Antoinette; Tumburu, Laxminath; Allwardt, Joshua M.; Miller, Jeffery L.

    2015-01-01

    Increasing fetal hemoglobin (HbF) levels in adult humans remains an active area in hematologic research. Here we explored erythroid-specific LIN28A expression for its effect in regulating gamma-globin gene expression and HbF levels in cultured adult erythroblasts. For this purpose, lentiviral transduction vectors were produced with LIN28A expression driven by erythroid-specific gene promoter regions of the human KLF1 or SPTA1 genes. Transgene expression of LIN28A with a linked puromycin resistance marker was restricted to the erythroid lineage as demonstrated by selective survival of erythroid colonies (greater than 95% of all colonies). Erythroblast LIN28A over-expression (LIN28A-OE) did not significantly affect proliferation or inhibit differentiation. Greater than 70% suppression of total let-7 microRNA levels was confirmed in LIN28A-OE cells. Increases in gamma-globin mRNA and protein expression with HbF levels reaching 30–40% were achieved. These data suggest that erythroblast targeting of LIN28A expression is sufficient for increasing fetal hemoglobin expression in adult human erythroblasts. PMID:26675483

  5. Sustainable Communities: A Lens for Envisioning and Achieving a Community-Based Culture of Social and Ecological Peace

    ERIC Educational Resources Information Center

    Verhagen, Frans C.

    2014-01-01

    One of the obstacles to dealing with the social and ecological crises that obstruct the achievement of a culture of peace is silo thinking in global governance. A unidimensional mode of planning, silo thinking leads to decisions based on the area of expertise of a particular agency or intergovernmental organization and fails to recognize linkages…

  6. Hype, harmony and human factors: applying user-centered design to achieve sustainable telehealth program adoption and growth.

    PubMed

    Rossos, P G; St-Cyr, O; Purdy, B; Toenjes, C; Masino, C; Chmelnitsky, D

    2015-01-01

    Despite decades of international experience with the use of information and communication technologies in healthcare delivery, widespread telehealth adoption remains limited and progress slow. Escalating health system challenges related to access, cost and quality currently coincide with rapid advancement of affordable and reliable internet based communication technologies creating unprecedented opportunities and incentives for telehealth. In this paper, we will describe how Human Factors Engineering (HFE) and user-centric elements have been incorporated into the establishment of telehealth within a large academic medical center to increase acceptance and sustainability. Through examples and lessons learned we wish to increase awareness of HFE and its importance in the successful implementation, innovation and growth of telehealth programs. PMID:25980714

  7. Flinders University School of Medicine, Northern Territory, Australia: Achieving Educational Excellence along with a Sustainable Rural Medical Workforce.

    PubMed

    Worley, Paul

    2008-10-01

    Introduction Medical schools today are being challenged to educate doctors who are willing and able to practice in areas of poverty and workforce need. In many countries, there is a shortage of doctors practicing in rural and remote communities. There is evidence that locating undergraduate medical education in rural areas increases the likelihood that graduates will choose to practice in underserved areas. Through its Parallel Rural Community Curriculum (PRCC), Flinders University School of Medicine (FUSM) now enables over 25% of its students to undertake an entire clinical year based in small rural communities supervised principally by rural family physicians. Objective The PRCC was conceived to provide a high quality educational intervention that would result in an increased number of students choosing to practice in rural and remote Australia. It was also designed to test the hypothesis that small rural and remote practices were capable of facilitating a full year of medical training at a standard comparable to that provided at a major tertiary hospital. Intervention Starting with eight students in four towns in 1997, the PRCC now places 30 students across 18 towns in rural Australia. The students simultaneously learn the disciplines of medicine, surgery, pediatrics, obstetrics and gynecology, psychiatry, and family medicine. At the end of the year, all Flinders students, regardless of training location, take the same comprehensive exam. Outcomes PRCC students improved their academic performance in comparison to their tertiary trained peers. This improvement has been consistent over the ten years studied. Seventy percent of the PRCC students have chosen to practice in rural locations, compared to 18 percent of tertiary-trained students. Over twelve years, the program has proved to be sustainable in a private practice environment with a workforce shortage. Conclusions Evaluation of the PRCC indicates that a rural community-based clinical education can provide a

  8. Moving Toward Universal Health Coverage (UHC) to Achieve Inclusive and Sustainable Health Development: Three Essential Strategies Drawn From Asian Experience

    PubMed Central

    Xu, Ye; Huang, Cheng; Colón-Ramos, Uriyoán

    2015-01-01

    Binagwaho and colleagues’ perspective piece provided a timely reflection on the experience of Rwanda in achieving the Millennium Development Goals (MDGs) and a proposal of 5 principles to carry forward in post-2015 health development. This commentary echoes their viewpoints and offers three lessons for health policy reforms consistent with these principles beyond 2015. Specifically, we argue that universal health coverage (UHC) is an integrated solution to advance the global health development agenda, and the three essential strategies drawn from Asian countries’ health reforms toward UHC are: (1) Public financing support and sequencing health insurance expansion by first extending health insurance to the extremely poor, vulnerable, and marginalized population are critical for achieving UHC; (2) Improved quality of delivered care ensures supply-side readiness and effective coverage; (3) Strategic purchasing and results-based financing creates incentives and accountability for positive changes. These strategies were discussed and illustrated with experience from China and other Asian economies. PMID:26673477

  9. Achieving Sustainability in a Semi-Arid Basin in Northwest Mexico through an Integrated Hydrologic-Economic-Institutional Model

    NASA Astrophysics Data System (ADS)

    Munoz-Hernandez, A.; Mayer, A. S.

    2008-12-01

    The hydrologic systems in Northwest Mexico are at risk of over exploitation due to poor management of the water resources and adverse climatic conditions. The purpose of this work is to create and Integrated Hydrologic-Economic-Institutional Model to support future development in the Yaqui River basin, well known by its agricultural productivity, by directing the water management practices toward sustainability. The Yaqui River basin is a semi-arid basin with an area of 72,000 square kilometers and an average precipitation of 527 mm per year. The primary user of water is agriculture followed by domestic use and industry. The water to meet user demands comes from three reservoirs constructed, in series, along the river. The main objective of the integrated simulation-optimization model is to maximize the economic benefit within the basin, subject to physical and environmental constraints. Decision variables include the water allocation to major users and reservoirs as well as aquifer releases. Economic and hydrologic (including the interaction of the surface water and groundwater) simulation models were both included in the integrated model. The surface water model refers to a rainfall-runoff model created, calibrated, and incorporated into a MATLAB code that estimates the monthly storage in the main reservoirs by solving a water balance. The rainfall-runoff model was coupled with a groundwater model of the Yaqui Valley which was previously developed (Addams, 2004). This model includes flow in the main canals and infiltration to the aquifer. The economic benefit of water for some activities such as agricultural use, domestic use, hydropower generation, and environmental value was determined. Sensitivity analysis was explored for those parameters that are not certain such as price elasticities or population growth. Different water allocation schemes were created based on climate change, climate variability, and socio-economic scenarios. Addams L. 2004. Water resource

  10. The role of the erythroid-specific delta-aminolevulinate synthase gene expression in erythroid heme synthesis.

    PubMed

    Meguro, K; Igarashi, K; Yamamoto, M; Fujita, H; Sassa, S

    1995-08-01

    Using antisense technology, the effects of suppressed gene expression of the erythroid-specific delta-aminolevulinate (ALA) synthase (ALAS-E) on heme synthesis, expression of mRNAs encoding an erythroid-specific transcription factor NF-E2, other heme pathway enzymes, and beta-globin were examined in murine erythroleukemia (MEL) cells. In MEL cells in which an antisense ALAS-E RNA was expressed (AS clone), sense ALAS-E mRNA levels in both untreated and dimethylsulfoxide (DMSO)-treated cells were decreased compared with their respective controls. Heme synthesis in AS clones was decreased in proportion to the suppressed levels of ALAS-E mRNA. In addition, mRNAs for ALA dehydratase, porphobilinogen deaminase, ferrochelatase (FeC), and beta-globin were also decreased in AS clones. There was a strong correlation between the level of ALAS-E mRNA and most of the mRNAs of the heme pathway enzymes and beta-globin. There was a decrease in the mRNA level of p45, but not of mafK, which are the large and the small subunits of NF-E2, respectively, in AS clones. Treatment of AS cells with hemin and ALA in the presence of DMSO partially restored the suppressed mRNA levels for beta-globin and FeC and heme content, respectively. These findings thus indicate that heme formation, which is determined by the level of ALAS-E, plays an essential role on gene expression of many proteins necessary for erythroid development. PMID:7620186

  11. RUNX1 represses the erythroid gene expression program during megakaryocytic differentiation.

    PubMed

    Kuvardina, Olga N; Herglotz, Julia; Kolodziej, Stephan; Kohrs, Nicole; Herkt, Stefanie; Wojcik, Bartosch; Oellerich, Thomas; Corso, Jasmin; Behrens, Kira; Kumar, Ashok; Hussong, Helge; Urlaub, Henning; Koch, Joachim; Serve, Hubert; Bonig, Halvard; Stocking, Carol; Rieger, Michael A; Lausen, Jörn

    2015-06-01

    The activity of antagonizing transcription factors represents a mechanistic paradigm of bidirectional lineage-fate control during hematopoiesis. At the megakaryocytic/erythroid bifurcation, the cross-antagonism of krueppel-like factor 1 (KLF1) and friend leukemia integration 1 (FLI1) has such a decisive role. However, how this antagonism is resolved during lineage specification is poorly understood. We found that runt-related transcription factor 1 (RUNX1) inhibits erythroid differentiation of murine megakaryocytic/erythroid progenitors and primary human CD34(+) progenitor cells. We show that RUNX1 represses the erythroid gene expression program during megakaryocytic differentiation by epigenetic repression of the erythroid master regulator KLF1. RUNX1 binding to the KLF1 locus is increased during megakaryocytic differentiation and counterbalances the activating role of T-cell acute lymphocytic leukemia 1 (TAL1). We found that corepressor recruitment by RUNX1 contributes to a block of the KLF1-dependent erythroid gene expression program. Our data indicate that the repressive function of RUNX1 influences the balance between erythroid and megakaryocytic differentiation by shifting the balance between KLF1 and FLI1 in the direction of FLI1. Taken together, we show that RUNX1 is a key player within a network of transcription factors that represses the erythroid gene expression program. PMID:25911237

  12. NF-E2 Overexpression Delays Erythroid Maturation and Increases Erythrocyte Production

    PubMed Central

    Mutschler, Manuel; Magin, Angela S.; Buerge, Martina; Roelz, Roland; Schanne, Daniel H.; Will, Britta; Pilz, Ingo H.; Migliaccio, Anna Rita; Pahl, Heike L.

    2009-01-01

    Summary The transcription factor Nuclear Factor-Erythroid 2 (NF-E2) is overexpressed in the vast majority of patients with polycythaemia vera (PV). In murine models, NF-E2 overexpression increases proliferation and promotes cellular viability in the absence of erythropoietin (EPO). EPO-independent growth is a hallmark of PV. We therefore hypothesized that NF-E2 overexpression contributes to erythrocytosis, the pathognomonic feature of PV. Consequently, we investigated the effect of NF-E2 overexpression in healthy CD34+ cells. NF-E2 overexpression led to a delay in erythroid maturation, manifested by a belated appearance of glycophorin A-positive erythroid precursors. Maturation delay was similarly observed in primary PV patient erythroid cultures compared to healthy controls. Protracted maturation led to a significant increase in the accumulated number of erythroid cells both in PV cultures and in CD34+ cells overexpressing NF-E2. Similarly, NF-E2 overexpression altered erythroid colony formation, leading to an increase in BFU-E formation. These data indicate that NF-E2 overexpression delays the early phase of erythroid maturation, resulting in an expansion of erythroid progenitors, thereby increasing the number of erythrocytes derived from one CD34+ cell. These data propose a role for NF-E2 in mediating the erythrocytosis of PV. PMID:19466964

  13. miR-150 inhibits terminal erythroid proliferation and differentiation

    PubMed Central

    Sun, Zhiwei; Wang, Ye; Han, Xu; Zhao, Xielan; Peng, Yuanliang; Li, Yusheng; Peng, Minyuan; Song, Jianhui; Wu, Kunlu; Sun, Shumin; Zhou, Weihua; Qi, Biwei; Zhou, Chufan; Chen, Huiyong; An, Xiuli; Liu, Jing

    2015-01-01

    MicroRNAs (miRNAs), a class of small non-coding linear RNAs, have been shown to play a crucial role in erythropoiesis. To evaluate the indispensable role of constant suppression of miR-150 during terminal erythropoiesis, we performed miR-150 gain- and loss-of-function experiments on hemin-induced K562 cells and EPO-induced human CD34+ cells. We found that forced expression of miR-150 suppresses commitment of hemoglobinization and CD235a labeling in both cell types. Erythroid proliferation is also inhibited via inducing apoptosis and blocking the cell cycle when miR-150 is overexpressed. In contrast, miR-150 inhibition promotes terminal erythropoiesis. 4.1 R gene is a new target of miR-150 during terminal erythropoiesis, and its abundance ensures the mechanical stability and deformability of the membrane. However, knockdown of 4.1 R did not affect terminal erythropoiesis. Transcriptional profiling identified more molecules involved in terminal erythroid dysregulation derived from miR-150 overexpression. These results shed light on the role of miR-150 during human terminal erythropoiesis. This is the first report highlighting the relationship between miRNA and membrane protein and enhancing our understanding of how miRNA works in the hematopoietic system. PMID:26543232

  14. Bmi-1 Regulates Extensive Erythroid Self-Renewal

    PubMed Central

    Kim, Ah Ram; Olsen, Jayme L.; England, Samantha J.; Huang, Yu-Shan; Fegan, Katherine H.; Delgadillo, Luis F.; McGrath, Kathleen E.; Kingsley, Paul D.; Waugh, Richard E.; Palis, James

    2015-01-01

    Summary Red blood cells (RBCs), responsible for oxygen delivery and carbon dioxide exchange, are essential for our well-being. Alternative RBC sources are needed to meet the increased demand for RBC transfusions projected to occur as our population ages. We previously have discovered that erythroblasts derived from the early mouse embryo can self-renew extensively ex vivo for many months. To better understand the mechanisms regulating extensive erythroid self-renewal, global gene expression data sets from self-renewing and differentiating erythroblasts were analyzed and revealed the differential expression of Bmi-1. Bmi-1 overexpression conferred extensive self-renewal capacity upon adult bone-marrow-derived self-renewing erythroblasts, which normally have limited proliferative potential. Importantly, Bmi-1 transduction did not interfere with the ability of extensively self-renewing erythroblasts (ESREs) to terminally mature either in vitro or in vivo. Bmi-1-induced ESREs can serve to generate in vitro models of erythroid-intrinsic disorders and ultimately may serve as a source of cultured RBCs for transfusion therapy. PMID:26028528

  15. Erythropoietin receptor signals both proliferation and erythroid-specific differentiation.

    PubMed Central

    Liboi, E; Carroll, M; D'Andrea, A D; Mathey-Prevot, B

    1993-01-01

    Ectopic expression of the erythropoietin receptor (EPO-R) in Ba/F3, an interleukin 3-dependent progenitor cell line, confers EPO-dependent cell growth. To examine whether the introduced EPO-R could affect differentiation, we isolated Ba/F3-EPO-R subclones in interleukin 3 and assayed for the induction of beta-globin mRNA synthesis after exposure to EPO. Detection of beta-globin mRNA was observed within 3 days of EPO treatment, with peak levels accumulating after 10 days. When EPO was withdrawn, expression of beta-globin mRNA persisted in most clones, suggesting that commitment to erythroid differentiation had occurred. Although EPO-R expression also supports EPO-dependent proliferation of CTLL-2, a mature T-cell line, those cells did not produce globin transcripts, presumably because they lack requisite cellular factors involved in erythrocyte differentiation. We conclude that the EPO-R transmits signals important for both proliferation and differentiation along the erythroid lineage. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8248252

  16. Experimental validation of predicted mammalian erythroid cis-regulatory modules

    PubMed Central

    Wang, Hao; Zhang, Ying; Cheng, Yong; Zhou, Yuepin; King, David C.; Taylor, James; Chiaromonte, Francesca; Kasturi, Jyotsna; Petrykowska, Hanna; Gibb, Brian; Dorman, Christine; Miller, Webb; Dore, Louis C.; Welch, John; Weiss, Mitchell J.; Hardison, Ross C.

    2006-01-01

    Multiple alignments of genome sequences are helpful guides to functional analysis, but predicting cis-regulatory modules (CRMs) accurately from such alignments remains an elusive goal. We predict CRMs for mammalian genes expressed in red blood cells by combining two properties gleaned from aligned, noncoding genome sequences: a positive regulatory potential (RP) score, which detects similarity to patterns in alignments distinctive for regulatory regions, and conservation of a binding site motif for the essential erythroid transcription factor GATA-1. Within eight target loci, we tested 75 noncoding segments by reporter gene assays in transiently transfected human K562 cells and/or after site-directed integration into murine erythroleukemia cells. Segments with a high RP score and a conserved exact match to the binding site consensus are validated at a good rate (50%–100%, with rates increasing at higher RP), whereas segments with lower RP scores or nonconsensus binding motifs tend to be inactive. Active DNA segments were shown to be occupied by GATA-1 protein by chromatin immunoprecipitation, whereas sites predicted to be inactive were not occupied. We verify four previously known erythroid CRMs and identify 28 novel ones. Thus, high RP in combination with another feature of a CRM, such as a conserved transcription factor binding site, is a good predictor of functional CRMs. Genome-wide predictions based on RP and a large set of well-defined transcription factor binding sites are available through servers at http://www.bx.psu.edu/. PMID:17038566

  17. Long-term follow-up of myelodysplastic syndrome patients with moderate/severe anaemia receiving human recombinant erythropoietin + 13-cis-retinoic acid and dihydroxylated vitamin D3: independent positive impact of erythroid response on survival.

    PubMed

    Crisà, Elena; Foli, Cristina; Passera, Roberto; Darbesio, Antonella; Garvey, Kimberly B; Boccadoro, Mario; Ferrero, Dario

    2012-07-01

    We previously reported a 60% erythroid response rate with recombinant erythropoietin + 13-cis retinoic acid + dihydroxylated vitamin D3 in 63 elderly myelodysplastic patients (median age 75 years) with unfavourable features for response to erythropoietin alone [70% transfusion-dependent, 35% refractory anaemia with ring sideroblasts/refractory anaemia with excess of blasts type 1 (RAEB1), 70% with International Prognostic Scoring System (IPSS) Intermediate-1 or -2]. This report updates that case study at a 7-year follow-up, and compared the impact on overall survival of erythroid response to known prognostic factors. The erythroid response duration (median 17 months; 22 in non-RAEB patients, with 20% patients in response after 6 years of therapy) was longer than in most studies with erythropoietin alone. Overall survival (median 55 months in non-RAEB, 15 in RAEB1 patients) was negatively affected by RAEB1 diagnosis, IPSS and WPSS intermediate scores and transfusion-dependence. In the multivariate analysis, erythroid response maintained an independent positive impact on survival, particularly in non-RAEB patients in the first 3 years from diagnosis (90% survival compared to 50% of non-responders). In conclusion, the long-term follow-up confirmed the achievement, by our combined treatment, of fairly long-lasting erythroid response in the majority of MDS patients with unfavourable prognostic features for response to erythropoietin: this translated in a survival benefit that was independent from other prognostic features. PMID:22571649

  18. The estrogen receptor cooperates with the TGF alpha receptor (c-erbB) in regulation of chicken erythroid progenitor self-renewal.

    PubMed

    Schroeder, C; Gibson, L; Nordström, C; Beug, H

    1993-03-01

    A unique combination of growth promoting factors is described that allows growth of large amounts (10(10)-10(11)) of normal erythroid progenitors from chick bone marrow. These erythroid progenitors express the estrogen receptor (ER) as well as the receptor tyrosine kinase TGF alpha R/c-erbB. They require both TGF alpha and estradiol for sustained self-renewal in vitro, but terminally differentiate upon withdrawal of TGF alpha and inactivation of the ER by an antagonist (ICI 164.384). Overexpression of the human ER in erythroblasts devoid of endogenous ER revealed that the hormone-activated ER alone arrested erythroid differentiation and repressed a large group of erythrocyte genes. When similarly overexpressed, TGF alpha R/c-erbB inhibited the expression of a distinct, but overlapping, set of genes. The endogenous ER and TGF alpha R/c-erbB affect erythrocyte gene expression in a similar, but less pronounced fashion. Surprisingly, suppression of ER function by antagonist efficiently inhibited erythroblast transformation by tyrosine kinase oncogenes, suggesting a role of the endogenous ER in leukemogenesis. We speculate that the oncogenes v-erbB and v-erbA cooperate in erythroleukemia induction by a mechanism that is employed by TGF alpha R/c-erbB and ER to regulate normal progenitor self-renewal in response to external signals. PMID:8458346

  19. The RNA binding protein RBM38 (RNPC1) regulates splicing during late erythroid differentiation.

    PubMed

    Heinicke, Laurie A; Nabet, Behnam; Shen, Shihao; Jiang, Peng; van Zalen, Sebastiaan; Cieply, Benjamin; Russell, J Eric; Xing, Yi; Carstens, Russ P

    2013-01-01

    Alternative pre-mRNA splicing is a prevalent mechanism in mammals that promotes proteomic diversity, including expression of cell-type specific protein isoforms. We characterized a role for RBM38 (RNPC1) in regulation of alternative splicing during late erythroid differentiation. We used an Affymetrix human exon junction (HJAY) splicing microarray to identify a panel of RBM38-regulated alternatively spliced transcripts. Using microarray databases, we noted high RBM38 expression levels in CD71(+) erythroid cells and thus chose to examine RBM38 expression during erythroid differentiation of human hematopoietic stem cells, detecting enhanced RBM38 expression during late erythroid differentiation. In differentiated erythroid cells, we validated a subset of RBM38-regulated splicing events and determined that RBM38 regulates activation of Protein 4.1R (EPB41) exon 16 during late erythroid differentiation. Using Epb41 minigenes, Rbm38 was found to be a robust activator of exon 16 splicing. To further address the mechanism of RBM38-regulated alternative splicing, a novel mammalian protein expression system, followed by SELEX-Seq, was used to identify a GU-rich RBM38 binding motif. Lastly, using a tethering assay, we determined that RBM38 can directly activate splicing when recruited to a downstream intron. Together, our data support the role of RBM38 in regulating alternative splicing during erythroid differentiation. PMID:24250749

  20. The RNA Binding Protein RBM38 (RNPC1) Regulates Splicing during Late Erythroid Differentiation

    PubMed Central

    Heinicke, Laurie A.; Nabet, Behnam; Shen, Shihao; Jiang, Peng; van Zalen, Sebastiaan; Cieply, Benjamin; Russell, J. Eric; Xing, Yi; Carstens, Russ P.

    2013-01-01

    Alternative pre-mRNA splicing is a prevalent mechanism in mammals that promotes proteomic diversity, including expression of cell-type specific protein isoforms. We characterized a role for RBM38 (RNPC1) in regulation of alternative splicing during late erythroid differentiation. We used an Affymetrix human exon junction (HJAY) splicing microarray to identify a panel of RBM38-regulated alternatively spliced transcripts. Using microarray databases, we noted high RBM38 expression levels in CD71+ erythroid cells and thus chose to examine RBM38 expression during erythroid differentiation of human hematopoietic stem cells, detecting enhanced RBM38 expression during late erythroid differentiation. In differentiated erythroid cells, we validated a subset of RBM38-regulated splicing events and determined that RBM38 regulates activation of Protein 4.1R (EPB41) exon 16 during late erythroid differentiation. Using Epb41 minigenes, Rbm38 was found to be a robust activator of exon 16 splicing. To further address the mechanism of RBM38-regulated alternative splicing, a novel mammalian protein expression system, followed by SELEX-Seq, was used to identify a GU-rich RBM38 binding motif. Lastly, using a tethering assay, we determined that RBM38 can directly activate splicing when recruited to a downstream intron. Together, our data support the role of RBM38 in regulating alternative splicing during erythroid differentiation. PMID:24250749

  1. Glutathione peroxidase 4 prevents necroptosis in mouse erythroid precursors

    PubMed Central

    Canli, Özge; Alankuş, Yasemin B.; Grootjans, Sasker; Vegi, Naidu; Hültner, Lothar; Hoppe, Philipp S.; Schroeder, Timm; Vandenabeele, Peter; Bornkamm, Georg W.

    2016-01-01

    Maintaining cellular redox balance is vital for cell survival and tissue homoeostasis because imbalanced production of reactive oxygen species (ROS) may lead to oxidative stress and cell death. The antioxidant enzyme glutathione peroxidase 4 (Gpx4) is a key regulator of oxidative stress–induced cell death. We show that mice with deletion of Gpx4 in hematopoietic cells develop anemia and that Gpx4 is essential for preventing receptor-interacting protein 3 (RIP3)-dependent necroptosis in erythroid precursor cells. Absence of Gpx4 leads to functional inactivation of caspase 8 by glutathionylation, resulting in necroptosis, which occurs independently of tumor necrosis factor α activation. Although genetic ablation of Rip3 normalizes reticulocyte maturation and prevents anemia, ROS accumulation and lipid peroxidation in Gpx4-deficient cells remain high. Our results demonstrate that ROS and lipid hydroperoxides function as not-yet-recognized unconventional upstream signaling activators of RIP3-dependent necroptosis. PMID:26463424

  2. Predictors and outcomes of sustained, intermittent or never achieving remission in patients with recent onset inflammatory polyarthritis: results from the Norfolk Arthritis Register

    PubMed Central

    Cook, Michael J.; Diffin, Janet; Scirè, Carlo A.; Lunt, Mark; MacGregor, Alex J.; Symmons, Deborah P. M.

    2016-01-01

    Objectives. Early remission is the current treatment strategy for patients with inflammatory polyarthritis (IP) and RA. Our objective was to identify baseline factors associated with achieving remission: sustained (SR), intermittent (IR) or never (NR) over a 5-year period in patients with early IP. Methods. Clinical and demographic data of patients with IP recruited to the Norfolk Arthritis Register (NOAR) were obtained at baseline and years 1, 2, 3 and 5. Remission was defined as no tender or swollen joints (out of 51). Patients were classified as NR or PR, respectively, if they were in remission at: no assessment or ⩾3 consecutive assessments after baseline, and IR otherwise. Ordinal regression and a random effects model, respectively, were used to examine the association between baseline factors, remission group and HAQ scores over time. Results. A total of 868 patients (66% female) were included. Of these, 54%, 34% and 12% achieved NR, IR and SR, respectively. In multivariate analysis, female sex (odds ratio, OR 0.47, 95% CI: 0.35, 0.63), higher tender joint count (OR = 0.94, 95% CI: 0.93, 0.96), higher HAQ (OR = 0.59, 95% CI: 0.48, 0.74), being obese (OR = 0.70, 95% CI: 0.50, 0.99), hypertensive (OR = 0.67, 95% CI: 0.50, 0.90) or depressed (OR = 0.74, 95% CI: 0.55, 1.00) at baseline were independent predictors of being in a lower remission group. IR and SR were associated with lower HAQ scores over time and lower DAS28 at year 5. Conclusion. Women with higher tender joint count and disability at baseline, depression, obesity and hypertension were less likely to achieve remission. This information could help when stratifying patients for more aggressive therapy. PMID:27220594

  3. Distinct Domains of the GATA-1 Cofactor FOG-1 Differentially Influence Erythroid versus Megakaryocytic Maturation

    PubMed Central

    Cantor, Alan B.; Katz, Samuel G.; Orkin, Stuart H.

    2002-01-01

    FOG family zinc finger proteins play essential roles in development through physical interaction with GATA factors. FOG-1, like its interacting partner GATA-1, is required for normal differentiation of erythroid and megakaryocytic cells. Here, we have developed a functional assay for FOG-1 based on its ability to rescue erythroid and megakaryocytic maturation of a genetically engineered FOG-1−/− cell line. We demonstrate that interaction through only one of FOG-1's four GATA-binding zinc fingers is sufficient for rescue, providing evidence against a model in which FOG-1 acts to bridge multiple GATA-binding DNA elements. Importantly, we find that distinct regions of FOG-1 differentially influence erythroid versus megakaryocyte maturation. As such, we propose that FOG-1 may modulate the fate of a bipotential erythroid/megakaryocytic precursor cell. PMID:12024038

  4. Assessment of erythroid dysplasia by "difference from normal" in routine clinical flow cytometry work-up.

    PubMed

    Eidenschink Brodersen, Lisa; Menssen, Andrew J; Wangen, Jamie R; Stephenson, Christine F; de Baca, Monica E; Zehentner, Barbara K; Wells, Denise A; Loken, Michael R

    2014-10-21

    Introduction: While multidimensional flow cytometry (MDF) has great utility in diagnostic work-ups of patients with suspected myelodysplastic syndromes (MDS), only the myeloid lineage has demonstrated reproducible abnormalities from multiple laboratories. With the effects of ammonium chloride (NH4 Cl) lysis on erythroid progenitors previously described, we applied this protocol to a patient cohort with diagnosed MDS to investigate phenotypic abnormalities that indicate erythroid dysplasia. Method: Bone marrow specimens [39 MDS, 9 acute myeloid leukemia (AML), 7 JAK2(V617F) positive myeloproliferative neoplasms (MPN), 5 nutritional deficiencies] were processed by NH4 Cl lysis and Ficoll preparation and evaluated by MDF using a difference from normal algorithm. Results: For the MDS cohort, phenotypic abnormalities on the mature erythroid progenitors were frequent for CD71 and CD36 (36% for each antigen); abnormalities for CD235a (8%) were observed. Among immature erythroid progenitors, abnormal maturation patterns (≤5%) and increased CD105 intensity (9%) were seen. Increased frequency of CD105 bright cells was observed (18%). While antigenic abnormalities correlated between NH4 Cl lysis and Ficoll preparation, the lysis method demonstrated the most consistent quantitative antigen intensities. Mean erythroid phenotypic abnormalities and prognostic cytogenetic subgroups correlated strongly. Morphologic and erythroid phenotypic abnormalities correlated, as did increasing FCSS and number of erythroid abnormalities, albeit without further increase for AML patients. Discussion: These data expand the understanding of erythropoiesis and define immunophenotypic abnormalities that indicate dyserythropoiesis in MDS utilizing a lysis protocol practical for routine implementation in clinical flow cytometric work-up. Preliminary studies also indicate strong correlation between phenotypic erythroid dysplasia and poor prognosis, as classified cytogenetically. © 2014 Clinical

  5. Differential regulation of the α-globin locus by Krüppel-like factor 3 in erythroid and non-erythroid cells

    PubMed Central

    2014-01-01

    Background Krüppel-like Factor 3 (KLF3) is a broadly expressed zinc-finger transcriptional repressor with diverse biological roles. During erythropoiesis, KLF3 acts as a feedback repressor of a set of genes that are activated by Krüppel-like Factor 1 (KLF1). Noting that KLF1 binds α-globin gene regulatory sequences during erythroid maturation, we sought to determine whether KLF3 also interacts with the α-globin locus to regulate transcription. Results We found that expression of a human transgenic α-globin reporter gene is markedly up-regulated in fetal and adult erythroid cells of Klf3−/− mice. Inspection of the mouse and human α-globin promoters revealed a number of canonical KLF-binding sites, and indeed, KLF3 was shown to bind to these regions both in vitro and in vivo. Despite these observations, we did not detect an increase in endogenous murine α-globin expression in Klf3 −/− erythroid tissue. However, examination of murine embryonic fibroblasts lacking KLF3 revealed significant de-repression of α-globin gene expression. This suggests that KLF3 may contribute to the silencing of the α-globin locus in non-erythroid tissue. Moreover, ChIP-Seq analysis of murine fibroblasts demonstrated that across the locus, KLF3 does not occupy the promoter regions of the α-globin genes in these cells, but rather, binds to upstream, DNase hypersensitive regulatory regions. Conclusions These findings reveal that the occupancy profile of KLF3 at the α-globin locus differs in erythroid and non-erythroid cells. In erythroid cells, KLF3 primarily binds to the promoters of the adult α-globin genes, but appears dispensable for normal transcriptional regulation. In non-erythroid cells, KLF3 distinctly binds to the HS-12 and HS-26 elements and plays a non-redundant, albeit modest, role in the silencing of α-globin expression. PMID:24885809

  6. Achieving sustained virologic response after interferon-free hepatitis C virus treatment correlates with hepatic interferon gene expression changes independent of cirrhosis.

    PubMed

    Meissner, E G; Kohli, A; Virtaneva, K; Sturdevant, D; Martens, C; Porcella, S F; McHutchison, J G; Masur, H; Kottilil, S

    2016-07-01

    Chronic hepatitis C virus (HCV) infection can now be treated with oral directly acting antiviral agents, either with or without ribavirin (RBV). Virologic relapse after treatment can occur, and in some studies was more common in cirrhotic subjects. We previously observed changes in hepatic immunity during interferon (IFN)-free therapy that correlated with favourable outcome in subjects with early liver disease. Here, we compared changes in endogenous IFN pathways during IFN-free, RBV-free therapy between cirrhotic and noncirrhotic subjects. mRNA and microRNA (miRNA) expression analyses were performed on paired pre- and post-treatment liver biopsies from genotype-1 HCV subjects treated with sofosbuvir/ledipasvir (SOF/LDV) for 12 weeks (n = 4, 3 cirrhotics) or SOF/LDV combined with GS-9669 or GS-9451 for 6 weeks (n = 6, 0 cirrhotics). Nine of ten subjects achieved a sustained virologic response (SVR), while one noncirrhotic subject relapsed. Hepatic IFN-stimulated gene expression decreased with treatment in the liver of all subjects, with no observable impact of cirrhosis. Hepatic gene expression of type III IFNs (IFNL1, IFNL3, IFNL4-ΔG) similarly decreased with treatment, while IFNA2 expression, undetectable in all subjects pretreatment, was detected post-treatment in three subjects who achieved a SVR. Only the subject who relapsed had detectable IFNL4-ΔG expression in post-treatment liver. Other IFNs had no change in gene expression (IFNG, IFNB1, IFNA5) or could not be detected. Although expression of multiple hepatic miRNAs changed with treatment, many miRNAs previously implicated in HCV replication and IFN signalling had unchanged expression. In conclusion, favourable treatment outcome during IFN-free HCV therapy is associated with changes in the host IFN response regardless of cirrhosis. PMID:26840694

  7. Age-related alterations in erythroid and granulopoietic progenitors in Diamond-Blackfan anaemia.

    PubMed

    Casadevall, N; Croisille, L; Auffray, I; Tchernia, G; Coulombel, L

    1994-06-01

    Mechanisms involved in the erythroid failure characterizing Diamond-Blackfan anaemia (DBA) remain unidentified. The general consensus is that the defect is intrinsic to the marrow erythroid progenitor, but the target progenitor cell has not been precisely identified, and in vitro studies have revealed considerable heterogeneity between patients. In order to understand better the meaning of such a biological heterogeneity, we examined the in vitro response of erythroid progenitors CFU-E (colony-forming unit-erythroid) and BFU-E (burst-forming unit-erythroid) to erythropoietin (Epo), interleukin-3 (IL-3) and stem cell factor (SCF) in a large series of 24 patients from 1 month to over 20 years of age. Results of colony assays revealed a striking correlation between the age of the patient and the extent of the abnormalities detected in vitro. Therefore, despite profound anaemia, 80% (7/10) of the patients studied within 1 year of diagnosis had normal numbers of both CFU-E and BFU-E which exhibited a normal response to cytokines. In contrast, 12/14 patients followed up for more than 3 years had decreased numbers of erythroid progenitors, in seven cases associated with decreased colony-forming unit granulocyte-macrophage (CFU-GM). The number of CFU-E and BFU-E was not normalized even by the addition of high concentrations of combined Epo, IL-3 and SCF.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7524624

  8. Tracking erythroid progenitor cells in times of need and times of plenty.

    PubMed

    Koury, Mark J

    2016-08-01

    Red blood cell production rates increase rapidly following blood loss or hemolysis, but the expansion of erythropoiesis in these anemic states is tightly regulated such that rebound polycythemia does not occur. The erythroid cells that respond to erythropoietic stimulation or suppression are the progenitor stages of burst-forming units-erythroid (BFU-Es) and colony-forming units-erythroid (CFU-Es). Results from an early study of the changes in the size, location, and cell cycling status of BFU-E and CFU-E populations in mice under normal conditions, erythropoietic stimulation, and erythropoietic suppression are used as reference points to review subsequent developments related to erythroid progenitor populations and regulation of their size. The review concerns development of erythroid progenitor populations mainly in mice and humans, with a focus on the mechanisms related to the rapid but highly regulated expansion of erythropoiesis in spleens of erythropoietically stimulated mice. Current knowledge is used as a model of erythroid progenitor populations in mice under normal, erythropoietically suppressed, and erythropoietically stimulated conditions. Clinical applications of information learned from studies of erythropoietic expansion, in terms of current therapies for anemia, are reviewed. PMID:26646992

  9. Histone Methyltransferase Setd8 Represses Gata2 Expression and Regulates Erythroid Maturation

    PubMed Central

    Malik, Jeffrey; Getman, Michael

    2015-01-01

    Setd8 is the sole histone methyltransferase in mammals capable of monomethylating histone H4 lysine 20 (H4K20me1). Setd8 is expressed at significantly higher levels in erythroid cells than any other cell or tissue type, suggesting that Setd8 has an erythroid-cell-specific function. To test this hypothesis, stable Setd8 knockdown was established in extensively self-renewing erythroblasts (ESREs), a well-characterized, nontransformed model of erythroid maturation. Knockdown of Setd8 resulted in impaired erythroid maturation characterized by a delay in hemoglobin accumulation, larger mean cell area, persistent ckit expression, incomplete nuclear condensation, and lower rates of enucleation. Setd8 knockdown did not alter ESRE proliferation or viability or result in accumulation of DNA damage. Global gene expression analyses following Setd8 knockdown demonstrated that in erythroid cells, Setd8 functions primarily as a repressor. Most notably, Gata2 expression was significantly higher in knockdown cells than in control cells and Gata2 knockdown rescued some of the maturation impairments associated with Setd8 disruption. Setd8 occupies critical regulatory elements in the Gata2 locus, and knockdown of Setd8 resulted in loss of H4K20me1 and gain of H4 acetylation at the Gata2 1S promoter. These results suggest that Setd8 is an important regulator of erythroid maturation that works in part through repression of Gata2 expression. PMID:25848090

  10. Repression by RB1 characterizes genes involved in the penultimate stage of erythroid development.

    PubMed

    Zhang, Ji; Loyd, Melanie R; Randall, Mindy S; Morris, John J; Shah, Jayesh G; Ney, Paul A

    2015-01-01

    Retinoblastoma-1 (RB1), and the RB1-related proteins p107 and p130, are key regulators of the cell cycle. Although RB1 is required for normal erythroid development in vitro, it is largely dispensable for erythropoiesis in vivo. The modest phenotype caused by RB1 deficiency in mice raises questions about redundancy within the RB1 family, and the role of RB1 in erythroid differentiation. Here we show that RB1 is the major pocket protein that regulates terminal erythroid differentiation. Erythroid cells lacking all pocket proteins exhibit the same cell cycle defects as those deficient for RB1 alone. RB1 has broad repressive effects on gene transcription in erythroid cells. As a group, RB1-repressed genes are generally well expressed but downregulated at the final stage of erythroid development. Repression correlates with E2F binding, implicating E2Fs in the recruitment of RB1 to repressed genes. Merging differential and time-dependent changes in expression, we define a group of approximately 800 RB1-repressed genes. Bioinformatics analysis shows that this list is enriched for terms related to the cell cycle, but also for terms related to terminal differentiation. Some of these have not been previously linked to RB1. These results expand the range of processes potentially regulated by RB1, and suggest that a principal role of RB1 in development is coordinating the events required for terminal differentiation. PMID:26397180

  11. Chelation efficacy and erythroid response during deferasirox treatment in patients with myeloproliferative neoplasms in fibrotic phase.

    PubMed

    Latagliata, Roberto; Montagna, Chiara; Porrini, Raffaele; Di Veroli, Ambra; Leonetti, Sabrina Crescenzi; Niscola, Pasquale; Ciccone, Fabrizio; Spadea, Antonio; Breccia, Massimo; Maurillo, Luca; Rago, Angela; Spirito, Francesca; Cedrone, Michele; De Muro, Marianna; Montanaro, Marco; Andriani, Alessandro; Bagnato, Antonino; Montefusco, Enrico; Alimena, Giuliana

    2016-06-01

    At present, very few data are available on deferasirox (DFX) in the treatment of patients with Philadelphia-negative myeloproliferative neoplasms in fibrotic phase (FP-MPN) and transfusion dependence. To address this issue, a retrospective analysis of 28 patients (22 male and 6 female) with FP-MPN and iron overload secondary to transfusion dependence was performed, based on patients enrolled in the database of our regional cooperative group who received treatment with DFX. DFX was started after a median interval from diagnosis of 12.8 months (IR 7.1-43.1) with median ferritin values of 1415 ng/mL (IR 1168-1768). Extra-hematological toxicity was reported in 16 of 28 patients (57.1%), but only two patients discontinued treatment due to toxicity. Among 26 patients evaluable for response (≥6 months of treatment), after a median treatment period of 15.4 months (IR 8.1-22.3), 11 patients (42.3%) achieved a stable and consistent reduction in ferritin levels <1000 ng/mL. As for hematological improvement, 6 of 26 patients (23%) showed a persistent (>3 months) rise of Hb levels >1.5 g/dL, with disappearance of transfusion dependence in four cases. Treatment with DFX is feasible and effective in FP-MPN with iron overload. Moreover, in this setting, an erythroid response can occur in a significant proportion of patients. PMID:26277477

  12. Chromatin looping as a target for altering erythroid gene expression.

    PubMed

    Krivega, Ivan; Dean, Ann

    2016-03-01

    The β-hemoglobinopathies are the most common monogenic disorders in humans, with symptoms arising after birth when the fetal γ-globin genes are silenced and the adult β-globin gene is activated. There is a growing appreciation that genome organization and the folding of chromosomes are key determinants of gene transcription. Underlying this function is the activity of transcriptional enhancers that increase the transcription of target genes over long linear distances. To accomplish this, enhancers engage in close physical contact with target promoters through chromosome folding or looping that is orchestrated by protein complexes that bind to both sites and stabilize their interaction. We find that enhancer activity can be redirected with concomitant changes in gene transcription. Both targeting the β-globin locus control region (LCR) to the γ-globin gene in adult erythroid cells by tethering and epigenetic unmasking of a silenced γ-globin gene lead to increased frequency of LCR/γ-globin contacts and reduced LCR/β-globin contacts. The outcome of these manipulations is robust, pancellular γ-globin transcription activation with a concomitant reduction in β-globin transcription. These examples show that chromosome looping may be considered a therapeutic target for gene activation in β-thalassemia and sickle cell disease. PMID:26918894

  13. Force Dependent Changes in Non-Erythroid Spectrin and Ankyrins

    NASA Astrophysics Data System (ADS)

    Degaga, Eleni; Forstner, Martin

    2012-02-01

    Mechanotransduction in cells describes the process by which external physical stimuli are converted into biochemical activity and plays an important role in many biological functions on both the cell and tissue level. However, the specific mechanisms by which mechanical forces lead to particular molecular and cellular responses are much less understood. We investigate the changes in non-erythroid spectrin and ankyrins as a result of equi-biaxial strain application to live cells in culture. Specifically, we focus on the spectrins' role in the ubiquitination process - a vital process in the regulation of protein degradation- of spectrin and ankyrins. We utilize immune-fluorescence staining and fluorescent fusion proteins for quantitative fluorescence imaging as well as biochemical methods to measure changes in of cell's spectrin and ankyrin content. Protein expression levels and localization between cells exposed to mechanical stimuli of different temporal and spatial profiles are compared. In addition, the threshold behavior of cell proliferation - as measured by number densities - of a variety of cell types as a function of mechano-stimulation is investigated.

  14. Myc Inhibits p27-Induced Erythroid Differentiation of Leukemia Cells by Repressing Erythroid Master Genes without Reversing p27-Mediated Cell Cycle Arrest▿ ‡

    PubMed Central

    Acosta, Juan C.; Ferrándiz, Nuria; Bretones, Gabriel; Torrano, Verónica; Blanco, Rosa; Richard, Carlos; O'Connell, Brenda; Sedivy, John; Delgado, M. Dolores; León, Javier

    2008-01-01

    Inhibition of differentiation has been proposed as an important mechanism for Myc-induced tumorigenesis, but the mechanisms involved are unclear. We have established a genetically defined differentiation model in human leukemia K562 cells by conditional expression of the cyclin-dependent kinase (Cdk) inhibitor p27 (inducible by Zn2+) and Myc (activatable by 4-hydroxy-tamoxifen). Induction of p27 resulted in erythroid differentiation, accompanied by Cdk inhibition and G1 arrest. Interestingly, activation of Myc inhibited p27-mediated erythroid differentiation without affecting p27-mediated proliferation arrest. Microarray-based gene expression indicated that, in the presence of p27, Myc blocked the upregulation of several erythroid-cell-specific genes, including NFE2, JUNB, and GATA1 (transcription factors with a pivotal role in erythropoiesis). Moreover, Myc also blocked the upregulation of Mad1, a transcriptional antagonist of Myc that is able to induce erythroid differentiation. Cotransfection experiments demonstrated that Myc-mediated inhibition of differentiation is partly dependent on the repression of Mad1 and GATA1. In conclusion, this model demonstrates that Myc-mediated inhibition of differentiation depends on the regulation of a specific gene program, whereas it is independent of p27-mediated cell cycle arrest. Our results support the hypothesis that differentiation inhibition is an important Myc tumorigenic mechanism that is independent of cell proliferation. PMID:18838534

  15. Myc inhibits p27-induced erythroid differentiation of leukemia cells by repressing erythroid master genes without reversing p27-mediated cell cycle arrest.

    PubMed

    Acosta, Juan C; Ferrándiz, Nuria; Bretones, Gabriel; Torrano, Verónica; Blanco, Rosa; Richard, Carlos; O'Connell, Brenda; Sedivy, John; Delgado, M Dolores; León, Javier

    2008-12-01

    Inhibition of differentiation has been proposed as an important mechanism for Myc-induced tumorigenesis, but the mechanisms involved are unclear. We have established a genetically defined differentiation model in human leukemia K562 cells by conditional expression of the cyclin-dependent kinase (Cdk) inhibitor p27 (inducible by Zn(2+)) and Myc (activatable by 4-hydroxy-tamoxifen). Induction of p27 resulted in erythroid differentiation, accompanied by Cdk inhibition and G(1) arrest. Interestingly, activation of Myc inhibited p27-mediated erythroid differentiation without affecting p27-mediated proliferation arrest. Microarray-based gene expression indicated that, in the presence of p27, Myc blocked the upregulation of several erythroid-cell-specific genes, including NFE2, JUNB, and GATA1 (transcription factors with a pivotal role in erythropoiesis). Moreover, Myc also blocked the upregulation of Mad1, a transcriptional antagonist of Myc that is able to induce erythroid differentiation. Cotransfection experiments demonstrated that Myc-mediated inhibition of differentiation is partly dependent on the repression of Mad1 and GATA1. In conclusion, this model demonstrates that Myc-mediated inhibition of differentiation depends on the regulation of a specific gene program, whereas it is independent of p27-mediated cell cycle arrest. Our results support the hypothesis that differentiation inhibition is an important Myc tumorigenic mechanism that is independent of cell proliferation. PMID:18838534

  16. Hydroxymethylcytosine and demethylation of the γ-globin gene promoter during erythroid differentiation.

    PubMed

    Ruiz, Maria Armila; Rivers, Angela; Ibanez, Vinzon; Vaitkus, Kestis; Mahmud, Nadim; DeSimone, Joseph; Lavelle, Donald

    2015-01-01

    The mechanism responsible for developmental stage-specific regulation of γ-globin gene expression involves DNA methylation. Previous results have shown that the γ-globin promoter is nearly fully demethylated during fetal liver erythroid differentiation and partially demethylated during adult bone marrow erythroid differentiation. The hypothesis that 5-hydroxymethylcytosine (5 hmC), a known intermediate in DNA demethylation pathways, is involved in demethylation of the γ-globin gene promoter during erythroid differentiation was investigated by analyzing levels of 5-methylcytosine (5 mC) and 5 hmC at a CCGG site within the 5' γ-globin gene promoter region in FACS-purified cells from baboon bone marrow and fetal liver enriched for different stages of erythroid differentiation. Our results show that 5 mC and 5 hmC levels at the γ-globin promoter are dynamically modulated during erythroid differentiation with peak levels of 5 hmC preceding and/or coinciding with demethylation. The Tet2 and Tet3 dioxygenases that catalyze formation of 5 hmC are expressed during early stages of erythroid differentiation and Tet3 expression increases as differentiation proceeds. In baboon CD34+ bone marrow-derived erythroid progenitor cell cultures, γ-globin expression was positively correlated with 5 hmC and negatively correlated with 5 mC at the γ-globin promoter. Supplementation of culture media with Vitamin C, a cofactor of the Tet dioxygenases, reduced γ-globin promoter DNA methylation and increased γ-globin expression when added alone and in an additive manner in combination with either DNA methyltransferase or LSD1 inhibitors. These results strongly support the hypothesis that the Tet-mediated 5 hmC pathway is involved in developmental stage-specific regulation of γ-globin expression by mediating demethylation of the γ-globin promoter. PMID:25932923

  17. Hydroxymethylcytosine and demethylation of the γ-globin gene promoter during erythroid differentiation

    PubMed Central

    Ruiz, Maria Armila; Rivers, Angela; Ibanez, Vinzon; Vaitkus, Kestis; Mahmud, Nadim; DeSimone, Joseph; Lavelle, Donald

    2015-01-01

    The mechanism responsible for developmental stage-specific regulation of γ-globin gene expression involves DNA methylation. Previous results have shown that the γ-globin promoter is nearly fully demethylated during fetal liver erythroid differentiation and partially demethylated during adult bone marrow erythroid differentiation. The hypothesis that 5-hydroxymethylcytosine (5hmC), a known intermediate in DNA demethylation pathways, is involved in demethylation of the γ-globin gene promoter during erythroid differentiation was investigated by analyzing levels of 5-methylcytosine (5mC) and 5hmC at a CCGG site within the 5′ γ-globin gene promoter region in FACS-purified cells from baboon bone marrow and fetal liver enriched for different stages of erythroid differentiation. Our results show that 5mC and 5hmC levels at the γ-globin promoter are dynamically modulated during erythroid differentiation with peak levels of 5hmC preceding and/or coinciding with demethylation. The Tet2 and Tet3 dioxygenases that catalyze formation of 5hmC are expressed during early stages of erythroid differentiation and Tet3 expression increases as differentiation proceeds. In baboon CD34+ bone marrow-derived erythroid progenitor cell cultures, γ-globin expression was positively correlated with 5hmC and negatively correlated with 5mC at the γ-globin promoter. Supplementation of culture media with Vitamin C, a cofactor of the Tet dioxygenases, reduced γ-globin promoter DNA methylation and increased γ-globin expression when added alone and in an additive manner in combination with either DNA methyltransferase or LSD1 inhibitors. These results strongly support the hypothesis that the Tet-mediated 5hmC pathway is involved in developmental stage-specific regulation of γ-globin expression by mediating demethylation of the γ-globin promoter. PMID:25932923

  18. Mitochondrial Hspa9/Mortalin regulates erythroid differentiation via iron-sulfur cluster assembly.

    PubMed

    Shan, Yuxi; Cortopassi, Gino

    2016-01-01

    Mitochondrial iron-sulfur cluster (ISC) biogenesis provides iron-sulfur cofactors to several mitochondrial proteins, but the extent to which ISC biogenesis regulates hematopoiesis has been unclear. The blood disease Myelodysplastic syndrome (MDS) is characterized by ineffective hematopoiesis, and the disease overlaps with the gene Hspa9/Mortalin in multiple ways: the HSPA9 locus maps to 5q31.2 that is frequently deleted in human MDS; mutant Hspa9 causes zebrafish MDS; and Hspa9 knockdown mice have decreased hematopoiesis. We show here that HSPA9 functions in mitochondrial ISC biogenesis, and is required for erythroid differentiation. HSPA9 interacts with and stabilizes the mitochondrial ISC biogenesis proteins frataxin, Nfs1, ISCU, and Nfu. MDS-causing mutations in HSPA9 protein change its interactions with ISC biogenesis proteins. Depletion of HSPA9 decreases aconitase activity, which requires an ISC at its active site, but not that of the non-ISC requiring malate dehydrogenase, and increases IRP1 binding activity. In erythroid cell lines, Hspa9 depletion inhibited erythroid differentiation, post-transcriptionally regulating the expression of Alas2 and FeCH, as expected through known ISC control of the IRE response elements in these genes. By contrast, the Alas2 open reading frame rescued the Hspa9-dependent defect in erythroid differentiation, but not when uncoupled from its 5'-IRE sequence. Thus, Hspa9 depletion causes a mitochondrial ISC deficit, altering IRP1-IRE binding and FeCH stability, which consequently inhibits Alas2 translation, heme synthesis, and erythroid differentiation, i.e.: Hspa9->ISC->IRP/IRE->Alas2->heme synthesis->erythroid differentiation. Thus Hspa9 regulates erythroid differentiation through ISC cluster assembly, providing a pathophysiological mechanism for an MDS subtype characterized by HSPA9 haploinsufficiency, and suggests hemin and other pharmacological stimulators of ISC synthesis as potential routes to therapy. PMID:26702583

  19. An Examination of Successful Leadership Behaviors Exhibited by Middle School Principals in Stimulating and Sustaining African-American Students' Achievement on the California Standards Test in Mathematics

    ERIC Educational Resources Information Center

    Williams, Jacqueline

    2013-01-01

    The purpose of this research study was to examine leadership behaviors of middle school principals who have been successful in stimulating and sustaining African-American students' mathematics achievement on the California Standards Test. Specifically, this research sought to answer the following questions: 1) How do middle school principal…

  20. Functional erythroid promoters created by interaction of the transcription factor GATA-1 with CACCC and AP-1/NFE-2 elements.

    PubMed Central

    Walters, M; Martin, D I

    1992-01-01

    We have investigated interactions between the erythroid transcription factor GATA-1 and factors binding two cis-acting elements commonly linked to GATA sites in erythroid control elements. GATA-1 is present at all stages of erythroid differentiation, is necessary for erythropoiesis, and binds sites in all erythroid control elements. However, minimal promoters containing GATA-1 sites are inactive when tested in erythroid cells. Based on this observation, two erythroid cis elements, here termed CACCC and AP-1/NFE-2, were linked to GATA sites in minimal promoters. None of the elements linked only to a TATA box created an active promoter, but GATA sites linked to either CACCC or AP-1/NFE-2 elements formed strong erythroid promoters. A mutation of T to C at position -175 in the gamma-globin promoter GATA site, associated with hereditary persistence of fetal hemoglobin (HPFH), increased expression of these promoters in both fetal and adult cells. A construct bearing the beta-globin CACCC element was more active in adult and less active in fetal erythroid cells, when compared with the gamma-globin CACCC element. These studies suggest that erythroid control elements are formed by the interactions of at least three transcription factors, none of which functions alone. Images PMID:1438231

  1. JAK-STAT and AKT pathway-coupled genes in erythroid progenitor cells through ontogeny

    PubMed Central

    2012-01-01

    Background It has been reported that the phosphatidylinositol 3-kinase (PI3K)-AKT signaling pathway regulates erythropoietin (EPO)-induced survival, proliferation, and maturation of early erythroid progenitors. Erythroid cell proliferation and survival have also been related to activation of the JAK-STAT pathway. The goal of this study was to observe the function of EPO activation of JAK-STAT and PI3K/AKT pathways in the development of erythroid progenitors from hematopoietic CD34+ progenitor cells, as well as to distinguish early EPO target genes in human erythroid progenitors during ontogeny. Methods Hematopoietic CD34+ progenitor cells, isolated from fetal and adult hematopoietic tissues, were differentiated into erythroid progenitor cells. We have used microarray analysis to examine JAK-STAT and PI3K/AKT related genes, as well as broad gene expression modulation in these human erythroid progenitor cells. Results In microarray studies, a total of 1755 genes were expressed in fetal liver, 3844 in cord blood, 1770 in adult bone marrow, and 1325 genes in peripheral blood-derived erythroid progenitor cells. The erythroid progenitor cells shared 1011 common genes. Using the Ingenuity Pathways Analysis software, we evaluated the network pathways of genes linked to hematological system development, cellular growth and proliferation. The KITLG, EPO, GATA1, PIM1 and STAT3 genes represent the major connection points in the hematological system development linked genes. Some JAK-STAT signaling pathway-linked genes were steadily upregulated throughout ontogeny (PIM1, SOCS2, MYC, PTPN11), while others were downregulated (PTPN6, PIAS, SPRED2). In addition, some JAK-STAT pathway related genes are differentially expressed only in some stages of ontogeny (STATs, GRB2, CREBB). Beside the continuously upregulated (AKT1, PPP2CA, CHUK, NFKB1) and downregulated (FOXO1, PDPK1, PIK3CG) genes in the PI3K-AKT signaling pathway, we also observed intermittently regulated gene expression

  2. Spatio-temporal optimization of agricultural practices to achieve a sustainable development at basin level; framework of a case study in Colombia

    NASA Astrophysics Data System (ADS)

    Uribe, Natalia; corzo, Gerald; Solomatine, Dimitri

    2016-04-01

    The flood events present during the last years in different basins of the Colombian territory have raised questions on the sensitivity of the regions and if this regions have common features. From previous studies it seems important features in the sensitivity of the flood process were: land cover change, precipitation anomalies and these related to impacts of agriculture management and water management deficiencies, among others. A significant government investment in the outreach activities for adopting and promoting the Colombia National Action Plan on Climate Change (NAPCC) is being carried out in different sectors and regions, having as a priority the agriculture sector. However, more information is still needed in the local environment in order to assess were the regions have this sensitivity. Also the continuous change in one region with seasonal agricultural practices have been pointed out as a critical information for optimal sustainable development. This combined spatio-temporal dynamics of crops cycle in relation to climate change (or variations) has an important impact on flooding events at basin areas. This research will develop on the assessment and optimization of the aggregated impact of flood events due to determinate the spatio-temporal dynamic of changes in agricultural management practices. A number of common best agricultural practices have been identified to explore their effect in a spatial hydrological model that will evaluate overall changes. The optimization process consists on the evaluation of best performance in the agricultural production, without having to change crops activities or move to other regions. To achieve this objectives a deep analysis of different models combined with current and future climate scenarios have been planned. An algorithm have been formulated to cover the parametric updates such that the optimal temporal identification will be evaluated in different region on the case study area. Different hydroinformatics

  3. Non-random subcellular distribution of variant EKLF in erythroid cells

    SciTech Connect

    Quadrini, Karen J.; Gruzglin, Eugenia; Bieker, James J.

    2008-04-15

    EKLF protein plays a prominent role during erythroid development as a nuclear transcription factor. Not surprisingly, exogenous EKLF quickly localizes to the nucleus. However, using two different assays we have unexpectedly found that a substantial proportion of endogenous EKLF resides in the cytoplasm at steady state in all erythroid cells examined. While EKLF localization does not appear to change during either erythroid development or terminal differentiation, we find that the protein displays subtle yet distinct biochemical and functional differences depending on which subcellular compartment it is isolated from, with PEST sequences possibly playing a role in these differences. Localization is unaffected by inhibition of CRM1 activity and the two populations are not differentiated by stability. Heterokaryon assays demonstrate that EKLF is able to shuttle out of the nucleus although its nuclear re-entry is rapid. These studies suggest there is an unexplored role for EKLF in the cytoplasm that is separate from its well-characterized nuclear function.

  4. Specific erythroid-lineage defect in mice conditionally deficient for Mediator subunit Med1.

    PubMed

    Stumpf, Melanie; Yue, Xiaojing; Schmitz, Sandra; Luche, Hervé; Reddy, Janardan K; Borggrefe, Tilman

    2010-12-14

    The Mediator complex forms the bridge between transcriptional activators and the RNA polymerase II. Med1 (also known as PBP or TRAP220) is a key component of Mediator that interacts with nuclear hormone receptors and GATA transcription factors. Here, we show dynamic recruitment of GATA-1, TFIIB, Mediator, and RNA polymerase II to the β-globin locus in induced mouse erythroid leukemia cells and in an erythropoietin-inducible hematopoietic progenitor cell line. Using Med1 conditional knockout mice, we demonstrate a specific block in erythroid development but not in myeloid or lymphoid development, highlighted by the complete absence of β-globin gene expression. Thus, Mediator subunit Med1 plays a pivotal role in erythroid development and in β-globin gene activation. PMID:21098667

  5. Non-random subcellular distribution of variant EKLF in erythroid cells.

    PubMed

    Quadrini, Karen J; Gruzglin, Eugenia; Bieker, James J

    2008-04-15

    EKLF protein plays a prominent role during erythroid development as a nuclear transcription factor. Not surprisingly, exogenous EKLF quickly localizes to the nucleus. However, using two different assays we have unexpectedly found that a substantial proportion of endogenous EKLF resides in the cytoplasm at steady state in all erythroid cells examined. While EKLF localization does not appear to change during either erythroid development or terminal differentiation, we find that the protein displays subtle yet distinct biochemical and functional differences depending on which subcellular compartment it is isolated from, with PEST sequences possibly playing a role in these differences. Localization is unaffected by inhibition of CRM1 activity and the two populations are not differentiated by stability. Heterokaryon assays demonstrate that EKLF is able to shuttle out of the nucleus although its nuclear re-entry is rapid. These studies suggest there is an unexplored role for EKLF in the cytoplasm that is separate from its well-characterized nuclear function. PMID:18329016

  6. Identification of a novel putative mitochondrial protein FAM210B associated with erythroid differentiation.

    PubMed

    Kondo, Aiko; Fujiwara, Tohru; Okitsu, Yoko; Fukuhara, Noriko; Onishi, Yasushi; Nakamura, Yukio; Sawada, Kenichi; Harigae, Hideo

    2016-04-01

    The transcription factor GATA-1 plays an essential role in erythroid differentiation. To identify novel GATA-1 target genes, we analyzed a merged ChIP-seq and expression profiling dataset. We identified FAM210B as a putative novel GATA-1 target gene. Study results demonstrated that GATA-1 directly regulates FAM210B expression, presumably by binding to an intronic enhancer region. Both human and murine FAM210B are abundantly expressed in the later stages of erythroblast development. Moreover, the deduced amino acid sequence predicted that FAM210B is a membrane protein, and Western blot analysis demonstrated its mitochondrial localization. Loss-of-function analysis in erythroid cells suggested that FAM210B may be involved in erythroid differentiation. The identification and characterization of FAM210B provides new insights in the study of erythropoiesis and hereditary anemias. PMID:26968549

  7. Interleukin-6 Directly Impairs the Erythroid Development of Human TF-1 Erythroleukemic Cells

    PubMed Central

    McCranor, Bryan J.; Kim, Min Jung; Cruz, Nicole M.; Xue, Qian-Li; Berger, Alan E.; Walston, Jeremy D.; Civin, Curt I.; Roy, Cindy N.

    2013-01-01

    Anemia of inflammation or chronic disease is a highly prevalent form of anemia. The inflammatory cytokine interleukin-6 (IL-6) negatively correlates with hemoglobin concentration in many disease states. The IL-6-hepcidin antimicrobial peptide axis promotes iron-restricted anemia; however the full role of IL-6 in anemia of inflammation is not well-defined. We previously reported that chronic inflammation had a negative impact on maturation of erythroid progenitors in a mouse model. We hypothesized that IL-6 may be responsible for impaired erythropoiesis, independent of iron restriction. To test the hypothesis we utilized the human erythroleukemia TF-1 cell line to model erythroid maturation and exposed them to varying doses of IL-6 over six days. At 10 ng/ml, IL-6 significantly repressed erythropoietin-dependent TF-1 erythroid maturation. While IL-6 did not decrease the expression of genes associated with hemoglobin synthesis, we observed impaired hemoglobin synthesis as demonstrated by decreased benzidine staining. We also observed that IL-6 down regulated expression of the gene SLC4a1 which is expressed late in erythropoiesis. Those findings suggested that IL-6-dependent inhibition of hemoglobin synthesis might occur. We investigated the impact of IL-6 on mitochondria. IL-6 decreased the mitochondrial membrane potential at all treatment doses, and significantly decreased mitochondrial mass at the highest dose. Our studies indicate that IL-6 may impair mitochondrial function in maturing erythroid cells resulting in impaired hemoglobin production and erythroid maturation. Our findings may indicate a novel pathway of action for IL-6 in the anemia of inflammation, and draw attention to the potential for new therapeutic targets that affect late erythroid development. PMID:24119518

  8. miR-451 regulates zebrafish erythroid maturation in vivo via its target gata2

    PubMed Central

    Pase, Luke; Layton, Judith E.; Kloosterman, Wigard P.; Carradice, Duncan; Waterhouse, Peter M.

    2009-01-01

    We demonstrate that in zebrafish, the microRNA miR-451 plays a crucial role in promoting erythroid maturation, in part via its target transcript gata2. Zebrafish miR-144 and miR-451 are processed from a single precursor transcript selectively expressed in erythrocytes. In contrast to other hematopoietic mutants, the zebrafish mutant meunier (mnr) showed intact erythroid specification but diminished miR-144/451 expression. Although erythropoiesis initiated normally in mnr, erythrocyte maturation was morphologically retarded. Morpholino knockdown of miR-451 increased erythrocyte immaturity in wild-type embryos, and miR-451 RNA duplexes partially rescued erythroid maturation in mnr, demonstrating a requirement and role for miR-451 in erythrocyte maturation. mnr provided a selectively miR-144/451-deficient background, facilitating studies to discern miRNA function and validate candidate targets. Among computer-predicted miR-451 targets potentially mediating these biologic effects, the pro-stem cell transcription factor gata2 was an attractive candidate. In vivo reporter assays validated the predicted miR-451/gata2-3′UTR interaction, gata2 down-regulation was delayed in miR-451-knockdown and mnr embryos, and gata2 knockdown partially restored erythroid maturation in mnr, collectively confirming gata2 down-regulation as pivotal for miR-451-driven erythroid maturation. These studies define a new genetic pathway promoting erythroid maturation (mnr/miR-451/gata2) and provide a rare example of partial rescue of a mutant phenotype solely by miRNA overexpression. PMID:18849488

  9. Regulation of erythroid differentiation by miR-376a and its targets

    PubMed Central

    Wang, Fang; Yu, Jia; Yang, Gui-Hua; Wang, Xiao-Shuang; Zhang, Jun-Wu

    2011-01-01

    Lineage differentiation is a continuous process during which fated progenitor cells execute specific programs to produce mature counterparts. This lineage-restricted pathway can be controlled by particular regulators, which are usually exclusively expressed in certain cell types or at specific differentiation stages. Here we report that miR-376a participates in the regulation of the early stages of human erythropoiesis by targeting cyclin-dependent kinase 2 (CDK2) and Argonaute 2 (Ago2). Among various human leukemia cell lines, miR-376a was only detected in K562 cells which originated from a progenitor common to the erythroid and megakaryotic lineages. Enforced expression of miR-376a or silencing of CDK2 and Ago2 by RNAi inhibits erythroid differentiation of K562 cells. Hematopoietic progenitor cells transduced with miR-376a showed a significant reduction of their erythroid clonogenic capacity. MiR-376a is relatively abundant in erythroid progenitor cells, where it reduces expression of CDK2 and maintains a low level of differentiation due to cell cycle arrest and decreased cell growth. Following erythroid induction, miR-376a is significantly down-regulated and CDK2 is released from miR-376a inhibition, thereby facilitating the escape of progenitor cells from the quiescent state into erythroid differentiation. Moreover, our results establish a functional link between miR-376a and Ago2, a key factor in miRNA biogenesis and silencing pathways with novel roles in human hematopoiesis. PMID:21556037

  10. Setd1a and NURF mediate chromatin dynamics and gene regulation during erythroid lineage commitment and differentiation

    PubMed Central

    Li, Ying; Schulz, Vincent P.; Deng, Changwang; Li, Guangyao; Shen, Yong; Tusi, Betsabeh K.; Ma, Gina; Stees, Jared; Qiu, Yi; Steiner, Laurie A.; Zhou, Lei; Zhao, Keji; Bungert, Jörg; Gallagher, Patrick G.; Huang, Suming

    2016-01-01

    The modulation of chromatin structure is a key step in transcription regulation in mammalian cells and eventually determines lineage commitment and differentiation. USF1/2, Setd1a and NURF complexes interact to regulate chromatin architecture in erythropoiesis, but the mechanistic basis for this regulation is hitherto unknown. Here we showed that Setd1a and NURF complexes bind to promoters to control chromatin structural alterations and gene activation in a cell context dependent manner. In human primary erythroid cells USF1/2, H3K4me3 and the NURF complex were significantly co-enriched at transcription start sites of erythroid genes, and their binding was associated with promoter/enhancer accessibility that resulted from nucleosome repositioning. Mice deficient for Setd1a, an H3K4 trimethylase, in the erythroid compartment exhibited reduced Ter119/CD71 positive erythroblasts, peripheral blood RBCs and hemoglobin levels. Loss of Setd1a led to a reduction of promoter-associated H3K4 methylation, inhibition of gene transcription and blockade of erythroid differentiation. This was associated with alterations in NURF complex occupancy at erythroid gene promoters and reduced chromatin accessibility. Setd1a deficiency caused decreased associations between enhancer and promoter looped interactions as well as reduced expression of erythroid genes such as the adult β-globin gene. These data indicate that Setd1a and NURF complexes are specifically targeted to and coordinately regulate erythroid promoter chromatin dynamics during erythroid lineage differentiation. PMID:27141965

  11. Pure Erythroid Leukemia Mimicking Ewing Sarcoma/Primitive Neuroectodermal Tumor in an Infant.

    PubMed

    Lapadat, Razvan; Tower, Richard L; Tam, Wayne; Orazi, Attilio; Gheorghe, Gabriela

    2016-05-01

    Pure erythroid leukemia (PEL) is a rare type of acute myeloid leukemia (AML) with a very aggressive clinical course. Presentation as a myeloid/erythroid sarcoma is exceedingly rare. We describe an infantile PEL presenting as a multifocal myeloid sarcoma, clinically and pathologically mimicking Ewing sarcoma/PNET family of tumors. The patient died 8 weeks after the initial presentation due to widespread disease. Our case shows that PEL needs to be considered in the differential diagnosis of small round blue cell tumors in infancy. A meticulous workup including immunohistochemistry, flow cytometry, molecular, and cytogenetic studies was required to reach the diagnosis. PMID:26773805

  12. Challenges facing the elimination of sleeping sickness in west and central Africa: sustainable control of animal trypanosomiasis as an indispensable approach to achieve the goal.

    PubMed

    Simo, Gustave; Rayaisse, Jean Baptiste

    2015-01-01

    African trypanosomiases are infectious diseases caused by trypanosomes. African animal trypanosomiasis (AAT) remains an important threat for livestock production in some affected areas whereas human African trypanosomiasis (HAT) is targeted for elimination in 2020. In West and Central Africa, it has been shown that the parasites causing these diseases can coexist in the same tsetse fly or the same animal. In such complex settings, the control of these diseases must be put in the general context of trypanosomiasis control or "one health" concept where the coordination of control operations will be beneficial for both diseases. In this context, implementing control activities on AAT will help to sustain HAT control. It will also have a positive impact on animal health and economic development of the regions. The training of inhabitants on how to implement and sustain vector control tools will enable a long-term sustainability of control operations that will lead to the elimination of HAT and AAT. PMID:26671582

  13. RESTORATION PLUS: A COLLABORATIVE RESEARCH PROGRAM TO DEVELOP AND EVALUATE ECOSYSTEM RESTORATION AND MANAGEMENT OPTIONS TO ACHIEVE ECOLOGICALLY AND ECONOMICALLY SUSTAINABLE SOLUTIONS

    EPA Science Inventory

    EPA is evaluating ecosystem restoration and management techniques to ensure they create sustainable solutions for degraded watersheds. ORD NRMRL initiated the Restoration Plus (RePlus) program in 2002 to a) evaluate ecosystem restoration and management options, b) assess the non-...

  14. RESTORATION PLUS: A COLLABORATIVE ENVIRONMENTAL PROTECTION AGENCY RESEARCH PROGRAM TO DEVELOP AND EVALUATE ECOSYSTEM RESTORATION AND MANAGEMENT OPTIONS TO ACHIEVE ECOLOGICALLY AND ECONOMICALLY SUSTAINABLE SOLUTIONS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (U.S. EPA) is evaluating ecosystem restoration and management techniques to ensure they create sustainable solutions for degraded watersheds. The ORD/NRMRL initiated the Restoration Plus (RePlus) program in 2002, which emphasizes collabora...

  15. Cytoplasmic poly(A) binding protein C4 serves a critical role in erythroid differentiation.

    PubMed

    Kini, Hemant K; Kong, Jian; Liebhaber, Stephen A

    2014-04-01

    The expression of an mRNA is strongly impacted by its 3' poly(A) tail and associated poly(A)-binding proteins (PABPs). Vertebrates encode six PABP isoforms that vary in abundance, distribution, developmental control, and subcellular localization. Here we demonstrate that the minor PABP isoform PABPC4 is expressed in erythroid cells and impacts the steady-state expression of a subset of erythroid mRNAs. Motif analyses reveal a high-value AU-rich motif in the 3' untranslated regions (UTRs) of PABPC4-impacted mRNAs. This motif enhances the association of PABPC4 with mRNAs containing critically shortened poly(A) tails. This association may serve to protect a subset of mRNAs from accelerated decay. Finally, we demonstrate that selective depletion of PABPC4 in an erythroblast cell line inhibits terminal erythroid maturation with corresponding alterations in the erythroid gene expression. These observations lead us to conclude that PABPC4 plays an essential role in posttranscriptional control of a major developmental pathway. PMID:24469397

  16. Histones to the cytosol: exportin 7 is essential for normal terminal erythroid nuclear maturation

    PubMed Central

    Martinez-Morilla, Sandra; Patterson, Heide Christine; Shi, Jiahai; Burke, Karly; Avila-Figueroa, Amalia; Venkatesan, Srividhya; Wang, Junxia; Paulsen, Katharina; Görlich, Dirk; Murata-Hori, Maki; Lodish, Harvey F.

    2014-01-01

    Global nuclear condensation, culminating in enucleation during terminal erythropoiesis, is poorly understood. Proteomic examination of extruded erythroid nuclei from fetal liver revealed a striking depletion of most nuclear proteins, suggesting that nuclear protein export had occurred. Expression of the nuclear export protein, Exportin 7 (Xpo7), is highly erythroid-specific, induced during erythropoiesis, and abundant in very late erythroblasts. Knockdown of Xpo7 in primary mouse fetal liver erythroblasts resulted in severe inhibition of chromatin condensation and enucleation but otherwise had little effect on erythroid differentiation, including hemoglobin accumulation. Nuclei in Xpo7-knockdown cells were larger and less dense than normal and accumulated most nuclear proteins as measured by mass spectrometry. Strikingly, many DNA binding proteins such as histones H2A and H3 were found to have migrated into the cytoplasm of normal late erythroblasts prior to and during enucleation, but not in Xpo7-knockdown cells. Thus, terminal erythroid maturation involves migration of histones into the cytoplasm via a process likely facilitated by Xpo7. PMID:25092175

  17. Insight into GATA1 transcriptional activity through interrogation of cis elements disrupted in human erythroid disorders.

    PubMed

    Wakabayashi, Aoi; Ulirsch, Jacob C; Ludwig, Leif S; Fiorini, Claudia; Yasuda, Makiko; Choudhuri, Avik; McDonel, Patrick; Zon, Leonard I; Sankaran, Vijay G

    2016-04-19

    Whole-exome sequencing has been incredibly successful in identifying causal genetic variants and has revealed a number of novel genes associated with blood and other diseases. One limitation of this approach is that it overlooks mutations in noncoding regulatory elements. Furthermore, the mechanisms by which mutations in transcriptionalcis-regulatory elements result in disease remain poorly understood. Here we used CRISPR/Cas9 genome editing to interrogate three such elements harboring mutations in human erythroid disorders, which in all cases are predicted to disrupt a canonical binding motif for the hematopoietic transcription factor GATA1. Deletions of as few as two to four nucleotides resulted in a substantial decrease (>80%) in target gene expression. Isolated deletions of the canonical GATA1 binding motif completely abrogated binding of the cofactor TAL1, which binds to a separate motif. Having verified the functionality of these three GATA1 motifs, we demonstrate strong evolutionary conservation of GATA1 motifs in regulatory elements proximal to other genes implicated in erythroid disorders, and show that targeted disruption of such elements results in altered gene expression. By modeling transcription factor binding patterns, we show that multiple transcription factors are associated with erythroid gene expression, and have created predictive maps modeling putative disruptions of their binding sites at key regulatory elements. Our study provides insight into GATA1 transcriptional activity and may prove a useful resource for investigating the pathogenicity of noncoding variants in human erythroid disorders. PMID:27044088

  18. Insight into GATA1 transcriptional activity through interrogation of cis elements disrupted in human erythroid disorders

    PubMed Central

    Wakabayashi, Aoi; Ulirsch, Jacob C.; Ludwig, Leif S.; Fiorini, Claudia; Yasuda, Makiko; Choudhuri, Avik; McDonel, Patrick; Zon, Leonard I.; Sankaran, Vijay G.

    2016-01-01

    Whole-exome sequencing has been incredibly successful in identifying causal genetic variants and has revealed a number of novel genes associated with blood and other diseases. One limitation of this approach is that it overlooks mutations in noncoding regulatory elements. Furthermore, the mechanisms by which mutations in transcriptional cis-regulatory elements result in disease remain poorly understood. Here we used CRISPR/Cas9 genome editing to interrogate three such elements harboring mutations in human erythroid disorders, which in all cases are predicted to disrupt a canonical binding motif for the hematopoietic transcription factor GATA1. Deletions of as few as two to four nucleotides resulted in a substantial decrease (>80%) in target gene expression. Isolated deletions of the canonical GATA1 binding motif completely abrogated binding of the cofactor TAL1, which binds to a separate motif. Having verified the functionality of these three GATA1 motifs, we demonstrate strong evolutionary conservation of GATA1 motifs in regulatory elements proximal to other genes implicated in erythroid disorders, and show that targeted disruption of such elements results in altered gene expression. By modeling transcription factor binding patterns, we show that multiple transcription factors are associated with erythroid gene expression, and have created predictive maps modeling putative disruptions of their binding sites at key regulatory elements. Our study provides insight into GATA1 transcriptional activity and may prove a useful resource for investigating the pathogenicity of noncoding variants in human erythroid disorders. PMID:27044088

  19. Regulation of alternative pre-mRNA splicing during erythroid differentiation.

    PubMed

    Hou, V C; Conboy, J G

    2001-03-01

    Although the mature enucleated erythrocyte is no longer active in nuclear processes such as pre-mRNA splicing, the function of many of its major structural proteins is dependent on alternative splicing choices made during the earlier stages of erythropoiesis. These splicing decisions fundamentally regulate many aspects of protein structure and function by governing the inclusion or exclusion of exons that encode protein interaction domains, regulatory signals, or translation initiation or termination sites. Alternative splicing events may be partially or entirely erythroid-specific, ie, distinct from the splicing patterns imposed on the same transcripts in nonerythroid cells. Moreover, differentiation stage-specific splicing "switches" may alter the structure and function of erythroid proteins in physiologically important ways as the cell is morphologically and functionally remodeled during normal differentiation. Derangements in the splicing of individual mutated pre-mRNAs can produce synthesis of truncated or unstable proteins that are responsible for numerous erythrocyte disorders. This review will summarize the salient features of regulated alternative splicing in general, review existing information concerning the widespread extent of alternative splicing among erythroid genes, and describe recent studies that are beginning to uncover the mechanisms that regulate an erythroid splicing switch in the protein 4.1R gene. PMID:11224680

  20. Ldb1-nucleated transcription complexes function as primary mediators of global erythroid gene activation.

    PubMed

    Li, LiQi; Freudenberg, Johannes; Cui, Kairong; Dale, Ryan; Song, Sang-Hyun; Dean, Ann; Zhao, Keji; Jothi, Raja; Love, Paul E

    2013-05-30

    Erythropoiesis is dependent on the lineage-specific transcription factors Gata1, Tal1, and Klf1. Several erythroid genes have been shown to require all 3 factors for their expression, suggesting that they function synergistically; however, there is little direct evidence for widespread cooperation. Gata1 and Tal1 can assemble within higher-order protein complexes (Ldb1 complexes) that include the adapter molecules Lmo2 and Ldb1. Ldb1 proteins are capable of coassociation, and long-range Ldb1-mediated oligomerization of enhancer- and promoter-bound Ldb1 complexes has been shown to be required for β-globin gene expression. In this study, we generated a genomewide map of Ldb1 complex binding sites that revealed widespread binding at erythroid genes and at known erythroid enhancer elements. Ldb1 complex binding sites frequently colocalized with Klf1 binding sites and with consensus binding motifs for other erythroid transcription factors. Transcriptomic analysis demonstrated a strong correlation between Ldb1 complex binding and Ldb1 dependency for gene expression and identified a large cohort of genes coregulated by Ldb1 complexes and Klf1. Together, these results provide a foundation for defining the mechanism and scope of Ldb1 complex activity during erythropoiesis. PMID:23610375

  1. Ldb1 complexes: the new master regulators of erythroid gene transcription.

    PubMed

    Love, Paul E; Warzecha, Claude; Li, LiQi

    2014-01-01

    Elucidation of the genetic pathways that control red blood cell development has been a central goal of erythropoiesis research over the past decade. Notably, data from several recent studies have provided new insights into the regulation of erythroid gene transcription. Transcription profiling demonstrates that erythropoiesis is mainly controlled by a small group of lineage-restricted transcription factors [Gata binding protein 1 (Gata1), T cell acute lymphocytic leukemia 1 protein (Tal1), and Erythroid Kruppel-like factor (EKLF; henceforth referred to as Klf1)]. Binding-site mapping using ChIP-Seq indicates that most DNA-bound Gata1 and Tal1 proteins are contained within higher order complexes (Ldb1 complexes) that include the nuclear adapters Ldb1 and Lmo2. Ldb1 complexes regulate Klf1, and Ldb1 complex-binding sites frequently colocalize with Klf1 at erythroid genes and cis-regulatory elements, indicating strong functional synergy between Gata1, Tal1, and Klf1. Together with new data demonstrating that Ldb1 can mediate long-range promoter-enhancer interactions, these findings provide a foundation for the first comprehensive models of the global regulation of erythroid gene transcription. PMID:24290192

  2. Cytotoxicity of quantum dots and graphene oxide to erythroid cells and macrophages

    NASA Astrophysics Data System (ADS)

    Qu, Guangbo; Wang, Xiaoyan; Wang, Zhe; Liu, Sijin; Jiang, Guibing

    2013-04-01

    Great concerns have been raised about the exposure and possible adverse influence of nanomaterials due to their wide applications in a variety of fields, such as biomedicine and daily lives. The blood circulation system and blood cells form an important barrier against invaders, including nanomaterials. However, studies of the biological effects of nanomaterials on blood cells have been limited and without clear conclusions thus far. In the current study, the biological influence of quantum dots (QDs) with various surface coating on erythroid cells and graphene oxide (GO) on macrophages was closely investigated. We found that QDs posed great damage to macrophages through intracellular accumulation of QDs coupled with reactive oxygen species generation, particularly for QDs coated with PEG-NH2. QD modified with polyethylene glycol-conjugated amine particles exerted robust inhibition on cell proliferation of J744A.1 macrophages, irrespective of apoptosis. Additionally, to the best of our knowledge, our study is the first to have demonstrated that GO could provoke apoptosis of erythroid cells through oxidative stress in E14.5 fetal liver erythroid cells and in vivo administration of GO-diminished erythroid population in spleen, associated with disordered erythropoiesis in mice.

  3. Cytoplasmic Poly(A) Binding Protein C4 Serves a Critical Role in Erythroid Differentiation

    PubMed Central

    Kini, Hemant K.; Kong, Jian

    2014-01-01

    The expression of an mRNA is strongly impacted by its 3′ poly(A) tail and associated poly(A)-binding proteins (PABPs). Vertebrates encode six PABP isoforms that vary in abundance, distribution, developmental control, and subcellular localization. Here we demonstrate that the minor PABP isoform PABPC4 is expressed in erythroid cells and impacts the steady-state expression of a subset of erythroid mRNAs. Motif analyses reveal a high-value AU-rich motif in the 3′ untranslated regions (UTRs) of PABPC4-impacted mRNAs. This motif enhances the association of PABPC4 with mRNAs containing critically shortened poly(A) tails. This association may serve to protect a subset of mRNAs from accelerated decay. Finally, we demonstrate that selective depletion of PABPC4 in an erythroblast cell line inhibits terminal erythroid maturation with corresponding alterations in the erythroid gene expression. These observations lead us to conclude that PABPC4 plays an essential role in posttranscriptional control of a major developmental pathway. PMID:24469397

  4. Probing conformational stability and dynamics of erythroid and nonerythroid spectrin: effects of urea and guanidine hydrochloride.

    PubMed

    Patra, Malay; Mukhopadhyay, Chaitali; Chakrabarti, Abhijit

    2015-01-01

    We have studied the conformational stability of the two homologous membrane skeletal proteins, the erythroid and non-erythroid spectrins, in their dimeric and tetrameric forms respectively during unfolding in the presence of urea and guanidine hydrochloride (GuHCl). Fluorescence and circular dichroism (CD) spectroscopy have been used to study the changes of intrinsic tryptophan fluorescence, anisotropy, far UV-CD and extrinsic fluorescence of bound 1-anilinonapthalene-8-sulfonic acid (ANS). Chemical unfolding of both proteins were reversible and could be described as a two state transition. The folded erythroid spectrin and non-erythroid spectrin were directly converted to unfolded monomer without formation of any intermediate. Fluorescence quenching, anisotropy, ANS binding and dynamic light scattering data suggest that in presence of low concentrations of the denaturants (up-to 1M) hydrogen bonding network and van der Waals interaction play a role inducing changes in quaternary as well as tertiary structures without complete dissociation of the subunits. This is the first report of two large worm like, multi-domain proteins obeying twofold rule which is commonly found in small globular proteins. The free energy of stabilization (ΔGuH20) for the dimeric spectrin has been 20 kcal/mol lesser than the tetrameric from. PMID:25617632

  5. Probing Conformational Stability and Dynamics of Erythroid and Nonerythroid Spectrin: Effects of Urea and Guanidine Hydrochloride

    PubMed Central

    Patra, Malay; Mukhopadhyay, Chaitali; Chakrabarti, Abhijit

    2015-01-01

    We have studied the conformational stability of the two homologous membrane skeletal proteins, the erythroid and non-erythroid spectrins, in their dimeric and tetrameric forms respectively during unfolding in the presence of urea and guanidine hydrochloride (GuHCl). Fluorescence and circular dichroism (CD) spectroscopy have been used to study the changes of intrinsic tryptophan fluorescence, anisotropy, far UV-CD and extrinsic fluorescence of bound 1-anilinonapthalene-8-sulfonic acid (ANS). Chemical unfolding of both proteins were reversible and could be described as a two state transition. The folded erythroid spectrin and non-erythroid spectrin were directly converted to unfolded monomer without formation of any intermediate. Fluorescence quenching, anisotropy, ANS binding and dynamic light scattering data suggest that in presence of low concentrations of the denaturants (up-to 1M) hydrogen bonding network and van der Waals interaction play a role inducing changes in quaternary as well as tertiary structures without complete dissociation of the subunits. This is the first report of two large worm like, multi-domain proteins obeying twofold rule which is commonly found in small globular proteins. The free energy of stabilization (ΔGuH20) for the dimeric spectrin has been 20 kcal/mol lesser than the tetrameric from. PMID:25617632

  6. Effects of THAP11 on Erythroid Differentiation and Megakaryocytic Differentiation of K562 Cells

    PubMed Central

    Kong, Xiang-Zhen; Yin, Rong-Hua; Ning, Hong-Mei; Zheng, Wei-Wei; Dong, Xiao-Ming; Yang, Yang; Xu, Fei-Fei; Li, Jian-Jie; Zhan, Yi-Qun; Yu, Miao; Ge, Chang-Hui; Zhang, Jian-Hong; Chen, Hui; Li, Chang-Yan; Yang, Xiao-Ming

    2014-01-01

    Hematopoiesis is a complex process regulated by sets of transcription factors in a stage-specific and context-dependent manner. THAP11 is a transcription factor involved in cell growth, ES cell pluripotency, and embryogenesis. Here we showed that THAP11 was down-regulated during erythroid differentiation but up-regulated during megakaryocytic differentiation of cord blood CD34+ cells. Overexpression of THAP11 in K562 cells inhibited the erythroid differentiation induced by hemin with decreased numbers of benzidine-positive cells and decreased mRNA levels of α-globin (HBA) and glycophorin A (GPA), and knockdown of THAP11 enhanced the erythroid differentiation. Conversely, THAP11 overexpression accelerated the megakaryocytic differentiation induced by phorbol myristate acetate (PMA) with increased percentage of CD41+ cells, increased numbers of 4N cells, and elevated CD61 mRNA levels, and THAP11 knockdown attenuated the megakaryocytic differentiation. The expression levels of transcription factors such as c-Myc, c-Myb, GATA-2, and Fli1 were changed by THAP11 overexpression. In this way, our results suggested that THAP11 reversibly regulated erythroid and megakaryocytic differentiation. PMID:24637716

  7. Narrowing the Achievement Gap and Sustaining Success: A Qualitative Study of the Norms, Practices, and Programs of a Successful High School with Urban Characteristics

    ERIC Educational Resources Information Center

    Senesac, Donald Raymond

    2010-01-01

    The academic achievement gap is the manifestation of differential learning outcomes for students typified by membership in an ethnic minority sub group or economically disadvantaged sub group. Addressing the achievement gap has become vital for the nation as a whole, and even more critical for the state of California because the majority of…

  8. Sustainable Development

    NASA Astrophysics Data System (ADS)

    Schmandt, Jurgen; Ward, C. H.; Marilu Hastings, Assisted By

    2000-04-01

    Demographers predict that the world population will double during the first half of the 21st century before it will begin to level off. In this volume, a group of prominent authors examine what societal changes must occur to meet this challenge to the natural environment and the transformational changes that we must experience to achieve sustainability. Frances Cairncross, Herman E. Daly, Stephen H. Schneider and others provide a broad discussion of sustainable development. They detail economic and environmental, as well as spiritual and religious, corporate and social, scientific and political factors. Sustainable Development: The Challenge of Transition offers many insightful policy recommendations about how business, government, and individuals must change their current values, priorities, and behavior to meet present and future challenges. It will appeal to scholars and decision makers interested in global change, environmental policy, population growth, and sustainable development, and also to corporate environmental managers.

  9. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin

    PubMed Central

    Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J.; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F.; Psathaki, Olympia E.; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R.; Schlenke, Peter; Zaehres, Holm

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34+ hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34+ hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34+ hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34+ cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. PMID:25326431

  10. Id2 intrinsically regulates lymphoid and erythroid development via interaction with different target proteins

    PubMed Central

    Ji, Ming; Li, Huajie; Suh, Hyung Chan; Klarmann, Kimberly D.; Yokota, Yoshifumi

    2008-01-01

    Inhibitors of DNA binding (Id) family members are key regulators of cellular differentiation and proliferation. These activities are related to the ability of Id proteins to antagonize E proteins and other transcription factors. As negative regulators of E proteins, Id proteins have been implicated in lymphocyte development. Overexpression of Id1, Id2, or Id3 has similar effects on lymphocyte development. However, which Id protein plays a physiologic role during lymphocyte development is not clear. By analyzing Id2 knock-out mice and retroviral transduced hematopoietic progenitors, we demonstrated that Id2 is an intrinsic negative regulator of B-cell development. Hematopoietic progenitor cells overexpressing Id2 did not reconstitute B-cell development in vivo, which resembled the phenotype of E2A null mice. The B-cell population in bone marrow was significantly expanded in Id2 knock-out mice compared with their wild-type littermates. Knock-down of Id2 by shRNA in hematopoietic progenitor cells promoted B-cell differentiation and induced the expression of B-cell lineage–specific genes. These data identified Id2 as a physiologically relevant regulator of E2A during B lymphopoiesis. Furthermore, we identified a novel Id2 function in erythroid development. Overexpression of Id2 enhanced erythroid development, and decreased level of Id2 impaired normal erythroid development. Id2 regulation of erythroid development is mediated via interacting with transcription factor PU.1 and modulating PU.1 and GATA-1 activities. We conclude that Id2 regulates lymphoid and erythroid development via interaction with different target proteins. PMID:18523151

  11. Leukemia-induced bone marrow depression: effects of gangliosides on erythroid cell production.

    PubMed

    Sietsma, H; Kamps, W A; Dontje, B; Hendriks, D; Kok, J W; Vellenga, E; Nijhof, W

    1999-07-01

    Bone marrow depression is a common feature in hematological malignancies or other bone marrow-involving cancers. The mechanism of this hemopoietic suppression resulting in pancytopenia and especially anemia has not been elucidated. Gangliosides can be shed by cancer cells. Therefore, we investigated the effects of exogenously added gangliosides on erythropoiesis in a human and murine in vitro system. A dose-dependent inhibition of murine colony-forming-unit-erythroid (CFU-E) and burst-forming-unit-erythroid (BFU-E) colony growth was observed. Furthermore the maturation of BFU-Es into CFU-Es was inhibited. The inhibition by gangliosides was not abolished by increasing the dose of erythropoietin (10 U/ml). FACS-analysis studies with human CD34+ cells cultured with gangliosides (GM3), erythropoietin (EPO) and stem cell factor (SCF) demonstrated a strong inhibition on cell growth. This resulted in a significantly higher percentage of immature cells (CD34+/GpA-, 24% vs. 3%), and a lower percentage of mature erythroid cells (CD34-/GpA+, 36% vs. 89%). Under these circumstances the effects on erythroid cell growth were much higher than on other cell lineages. The inhibitory effect of gangliosides isolated from acute lymphoblastic leukemic patients on in vitro erythropoiesis suggests that in vivo hemopoietic suppression might have its origin in the gangliosides present and probably shed by the malignant cells in the microenvironment and plasma. Our results show that gangliosides inhibit erythropoiesis in vitro at several stages of development, by a mechanism involving modulation of the maturation of erythroid cells. PMID:10360826

  12. Methylation of alpha-type embryonic globin gene alpha pi represses transcription in primary erythroid cells.

    PubMed

    Singal, Rakesh; vanWert, Jane M; Ferdinand, Larry

    2002-12-01

    The inverse relationship between expression and methylation of beta-type globin genes is well established. However, little is known about the relationship between expression and methylation of avian alpha-type globin genes. The embryonic alpha(pi)-globin promoter was unmethylated, and alpha(pi)-globin RNA was easily detected in 5-day chicken erythroid cells. A progressive methylation of the CpG dinucleotides in the alpha(pi) promoter associated with loss of expression of alpha(pi)-globin gene was seen during development in primary erythroid cells. A 315-bp alpha(pi)-globin promoter region was cloned in an expression construct (alpha(pi)pGL3E) containing a luciferase reporter gene and SV40 enhancer. The alpha(pi)pGL3E construct was transfected into primary erythroid cells derived from 5-day-old chicken embryos. Methylation of alpha(pi)pGL3E plasmid and alpha(pi)-globin promoter alone resulted in a 20-fold and 7-fold inhibition of expression, respectively. The fully methylated but not the unmethylated 315-bp alpha(pi)-globin gene promoter fragment formed a methyl cytosine-binding protein complex (MeCPC). Chromatin immunoprecipitation assays were combined with quantitative real-time polymerase chain reaction to assess histone acetylation associated with the alpha(pi)-globin gene promoter. Slight hyperacetylation of histone H3 but a marked hyperacetylation of histone H4 was seen in 5-day when compared with 14-day erythroid cells. These results demonstrate that methylation can silence transcription of an avian alpha-type embryonic globin gene in homologous primary erythroid cells, possibly by interacting with an MeCPC and histone deacetylase complex. PMID:12393573

  13. The role of catechol-O-methyltransferase in catechol-enhanced erythroid differentiation of K562 cells

    SciTech Connect

    Suriguga,; Li, Xiao-Fei; Li, Yang; Yu, Chun-Hong; Li, Yi-Ran; Yi, Zong-Chun

    2013-12-15

    Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependent increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation. - Highlights: • Catechol enhanced hemin-induced hemoglobin accumulation. • COMT-catalyzed methylation acted as detoxication of catechol. • COMT involved in catechol-enhanced erythroid differentiation.

  14. Three Years Sustained Complete Remission Achieved in a Primary Refractory ALK-Positive Anaplastic T Large Cell Lymphoma Treated with Crizotinib

    PubMed Central

    Mahuad, Carolina Valeria; Repáraz, María de los Ángeles Vicente; Zerga, Marta E.; Aizpurua, María Florencia; Casali, Claudia; Garate, Gonzalo

    2016-01-01

    The prognosis of the primary refractory anaplastic lymphoma kinase (ALK+) anaplastic T large cell lymphoma is ominous. The identification of molecular targets with potential to drive oncogenesis remains a cornerstone for the designing of new selective cancer therapies. Crizotinib is a selective ATP-competitive inhibitor for ALK, approved for its use in lung cancer with rearrangements on ALK gene. The reported cases describe the use of crizotinib as a bridging strategy prior to allotransplantation; there are no reported prolonged survivals under monotherapy with Crizotinib. We report a case of a primary refractory ALK+ anaplastic large-cell lymphoma that sustains complete response after 3 years of crizotinib monotherapy.

  15. Three Years Sustained Complete Remission Achieved in a Primary Refractory ALK-Positive Anaplastic T Large Cell Lymphoma Treated with Crizotinib.

    PubMed

    Mahuad, Carolina Valeria; Repáraz, María de Los Ángeles Vicente; Zerga, Marta E; Aizpurua, María Florencia; Casali, Claudia; Garate, Gonzalo

    2016-06-28

    The prognosis of the primary refractory anaplastic lymphoma kinase (ALK+) anaplastic T large cell lymphoma is ominous. The identification of molecular targets with potential to drive oncogenesis remains a cornerstone for the designing of new selective cancer therapies. Crizotinib is a selective ATP-competitive inhibitor for ALK, approved for its use in lung cancer with rearrangements on ALK gene. The reported cases describe the use of crizotinib as a bridging strategy prior to allotransplantation; there are no reported prolonged survivals under monotherapy with Crizotinib. We report a case of a primary refractory ALK+ anaplastic large-cell lymphoma that sustains complete response after 3 years of crizotinib monotherapy. PMID:27441079

  16. Globin gene expression in correlation with G protein-related genes during erythroid differentiation

    PubMed Central

    2013-01-01

    Background The guanine nucleotide binding protein (G protein)-coupled receptors (GPCRs) regulate cell growth, proliferation and differentiation. G proteins are also implicated in erythroid differentiation, and some of them are expressed principally in hematopoietic cells. GPCRs-linked NO/cGMP and p38 MAPK signaling pathways already demonstrated potency for globin gene stimulation. By analyzing erythroid progenitors, derived from hematopoietic cells through in vitro ontogeny, our study intends to determine early markers and signaling pathways of globin gene regulation and their relation to GPCR expression. Results Human hematopoietic CD34+ progenitors are isolated from fetal liver (FL), cord blood (CB), adult bone marrow (BM), peripheral blood (PB) and G-CSF stimulated mobilized PB (mPB), and then differentiated in vitro into erythroid progenitors. We find that growth capacity is most abundant in FL- and CB-derived erythroid cells. The erythroid progenitor cells are sorted as 100% CD71+, but we did not find statistical significance in the variations of CD34, CD36 and GlyA antigens and that confirms similarity in maturation of studied ontogenic periods. During ontogeny, beta-globin gene expression reaches maximum levels in cells of adult blood origin (176 fmol/μg), while gamma-globin gene expression is consistently up-regulated in CB-derived cells (60 fmol/μg). During gamma-globin induction by hydroxycarbamide, we identify stimulated GPCRs (PTGDR, PTGER1) and GPCRs-coupled genes known to be activated via the cAMP/PKA (ADIPOQ), MAPK pathway (JUN) and NO/cGMP (PRPF18) signaling pathways. During ontogeny, GPR45 and ARRDC1 genes have the most prominent expression in FL-derived erythroid progenitor cells, GNL3 and GRP65 genes in CB-derived cells (high gamma-globin gene expression), GPR110 and GNG10 in BM-derived cells, GPR89C and GPR172A in PB-derived cells, and GPR44 and GNAQ genes in mPB-derived cells (high beta-globin gene expression). Conclusions These results

  17. Follistatin-like 1 attenuates differentiation and survival of erythroid cells through Smad2/3 signaling.

    PubMed

    Wu, Jianping; Dong, Yingying; Teng, Xiaomei; Cheng, Maohua; Shen, Zhenya; Chen, Weiqian

    2015-10-30

    Hematopoiesis is a complex process tightly controlled by sets of transcription factors in a context-dependent and stage-specific manner. Smad2/3 transcription factor plays a central role in differentiation and survival of erythroid cells. Here we report that follistatin-like 1 (FSTL1) treatment impairs hemin-induced erythroid differentiation and cell survival. FSTL1 differentially regulates transforming growth factor beta (TGF-β) and bone morphogenetic protein (BMP) signaling. Blockade of Smad2/3 signaling with the ALK5/type I TGF-βR kinase inhibitor, SB-525334, was efficacious for rescue of erythroid differentiation blockage and apoptosis. Reversely, activation of Smad1/5/8 signaling with BMP4 cannot rescue FSTL1-mediated erythroid differentiation blockage and apoptosis. Collectively, these data provide mechanistic insight into the regulation of erythropoiesis by FSTL1 signaling and lay a foundation for exploring FSTL1 signaling as a therapeutic target for anemia. PMID:26365350

  18. Long-Term Treatment Outcomes of Patients Infected With Hepatitis C Virus: A Systematic Review and Meta-analysis of the Survival Benefit of Achieving a Sustained Virological Response

    PubMed Central

    Simmons, Bryony; Saleem, Jawaad; Heath, Katherine; Cooke, Graham S.; Hill, Andrew

    2015-01-01

    Background. Achievement of a sustained virologic response (SVR) after treatment for Hepatitis C infection is associated with improved outcomes. This meta-analysis aimed to determine the impact of SVR on long-term mortality risk compared with nonresponders in a range of populations. Methods. An electronic search identified all studies assessing all-cause mortality in SVR and non-SVR patients. Eligible articles were stratified into general, cirrhotic, and populations coinfected with human immunodeficiency virus. The adjusted hazard ratio (95% confidence interval [CI]) for mortality in patients achieving SVR vs non-SVR, and pooled estimates for the 5-year mortality in each group were calculated. Results. 31 studies (n = 33 360) were identified as suitable for inclusion. Median follow-up time was 5.4 years (interquartile range, 4.9–7.5) across all studies. The adjusted hazard ratio of mortality for patients achieving SVR vs non-SVR was 0.50 (95% CI, .37–.67) in the general population, 0.26 (95% CI, .18–.74) in the cirrhotic group, and 0.21 (.10–.45) in the coinfected group. The pooled 5-year mortality rates were significantly lower for patients achieving SVR compared with non-SVR in all 3 populations. Conclusions. The results suggest that there is a significant survival benefit of achieving an SVR compared with unsuccessful treatment in a range of populations infected with hepatitis C virus. PMID:25987643

  19. A qualitative and quantitative cytochemical assay of dihydrofolate reductase in erythroid cells.

    PubMed

    Nano, R; Gerzeli, G; Invernizzi, R; Supino, R

    1989-01-01

    The distribution and intensity of dihydrofolate reductase (DHFR) cytochemically demonstrable was studied in erythroid cells. Cells of normal human bone marrow, of human erythroleukaemia (M6), and cells of the Friend (MEL) clone 745A murine erythroleukaemia (also after differentiation with dimethylsulphoxide, DMSO) were stained according to Gerzeli and de Piceis Polver (1969) technique; quantification of the reaction product was made using a Vickers M86 microdensitometer. The enzyme activity progressively decreased during the normal differentiation of the erythropoietic series while persisted at high levels in erythroleukaemia cells. It can be suggested that in the 1st case, the cytochemical pattern of dihydrofolate reductase may be a useful added tool for studying the erythroid differentiation. In the 2nd case, the increased level of this enzyme may be related to an amplification of the gene of DHFR in the malignant transformation. PMID:2496572

  20. The presence of erythroid cells in the thymus gland of man.

    PubMed Central

    Kendall, M D; Singh, J

    1980-01-01

    Biopsies of the right lobe of normal thymus glands without signs of neoplasia or germinal centre formation from 35 patients ranging in age from 20 to 60 years of age, and from 3 children aged 6, 7 and 12, showed on electron microscopic examination of the material from 14 patients that in 12 cases erythroid cells of all stages of development past the beginning of haemoglobinisation were present in some degree. Earlier erythroid cells could not be identified on morphological grounds with certainty, but cells which could have been lymphoblasts, proerythroblasts and stem cell were all observed. A section of a megakaryocyte was seen in one thymus. The importance of erythropoiesis within the thymus gland is briefly discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:7364659

  1. Hematopoiesis and aging. IV. Mass and distribution of erythroid marrow in aged mice

    SciTech Connect

    Boggs, D.R.

    1985-11-01

    Aged mice are ''anemic,'' i.e., they have a lower hematocrit than young adult mice, but this appears to be a ''dilutional'' anemia; the red cell mass is normal. Other observations have supported the hypothesis that basal erythropoiesis does not change as mice grow old. In the present study, the percentage of injected VZFe found in the skeleton and spleen, VZFe distribution between various bones and bone groups, and the number of nucleated erythroid cells per humerus were studied and the total mass of erythroid precursors was calculated. There was no significant difference in any of these values between mice aged 3-27 months. The variability of VZFe distribution within various skeletal parts was no greater in aged than in young mice. Thus, these data further strengthen the case for normal basal rates of erythropoiesis in aged mice.

  2. TRAIL regulates normal erythroid maturation through an ERK-dependent pathway.

    PubMed

    Secchiero, Paola; Melloni, Elisabetta; Heikinheimo, Markku; Mannisto, Susanna; Di Pietro, Roberta; Iacone, Antonio; Zauli, Giorgio

    2004-01-15

    In order to investigate the biologic activity of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on human erythropoiesis, glycophorin A (GPA)+ erythroid cells were generated in serum-free liquid phase from human cord blood (CB) CD34+ progenitor cells. The surface expression of TRAIL-R1 was weakly detectable in the early-intermediate phase of erythroid differentiation (days 4-6; dim-intermediate GPA expression), whereas a clear-cut expression of TRAIL-R2 was observed through the entire course of erythroid differentiation (up to days 12-14; bright GPA expression). On the other hand, surface TRAIL-R3 and -R4 were not detected at any culture time. Besides inducing a rapid but small increase of apoptotic cell death, which was abrogated by the pan-caspase inhibitor z-VAD-fmk, the addition of recombinant TRAIL at day 6 of culture inhibited the generation of morphologically mature erythroblasts. Among the intracellular pathways investigated, TRAIL significantly stimulated the extracellular signal-regulated kinase 1/2 (ERK1/2) but not the p38/mitogen-activated protein kinase (MAPK) or the c-Jun NH2-terminal kinase (JNK) pathway. Consistently with a key role of ERK1/2 in mediating the negative effects of TRAIL on erythroid maturation, PD98059, a pharmacologic inhibitor of the ERK pathway, but not z-VAD-fmk or SB203580, a pharmacologic inhibitor of p38/MAPK, reverted the antidifferentiative effect of TRAIL on CB-derived erythroblasts. PMID:12969966

  3. RHEX, a novel regulator of human erythroid progenitor cell expansion and erythroblast development.

    PubMed

    Verma, Rakesh; Su, Su; McCrann, Donald J; Green, Jennifer M; Leu, Karen; Young, Peter R; Schatz, Peter J; Silva, Jeffrey C; Stokes, Matthew P; Wojchowski, Don M

    2014-08-25

    Ligation of erythropoietin (EPO) receptor (EPOR) JAK2 kinase complexes propagates signals within erythroid progenitor cells (EPCs) that are essential for red blood cell production. To reveal hypothesized novel EPOR/JAK2 targets, a phosphotyrosine (PY) phosphoproteomics approach was applied. Beyond known signal transduction factors, 32 new targets of EPO-modulated tyrosine phosphorylation were defined. Molecular adaptors comprised one major set including growth factor receptor-bound protein 2 (GRB2)-associated binding proteins 1-3 (GAB1-3), insulin receptor substrate 2 (IRS2), docking protein 1 (DOK1), Src homology 2 domain containing transforming protein 1 (SHC1), and sprouty homologue 1 (SPRY1) as validating targets, and SPRY2, SH2 domain containing 2A (SH2D2A), and signal transducing adaptor molecule 2 (STAM2) as novel candidate adaptors together with an ORF factor designated as regulator of human erythroid cell expansion (RHEX). RHEX is well conserved in Homo sapiens and primates but absent from mouse, rat, and lower vertebrate genomes. Among tissues and lineages, RHEX was elevated in EPCs, occurred as a plasma membrane protein, was rapidly PY-phosphorylated >20-fold upon EPO exposure, and coimmunoprecipitated with the EPOR. In UT7epo cells, knockdown of RHEX inhibited EPO-dependent growth. This was associated with extracellular signal-regulated kinase 1,2 (ERK1,2) modulation, and RHEX coupling to GRB2. In primary human EPCs, shRNA knockdown studies confirmed RHEX regulation of erythroid progenitor expansion and further revealed roles in promoting the formation of hemoglobinizing erythroblasts. RHEX therefore comprises a new EPO/EPOR target and regulator of human erythroid cell expansion that additionally acts to support late-stage erythroblast development. PMID:25092874

  4. Regulatory elements of the EKLF gene that direct erythroid cell-specific expression during mammalian development.

    PubMed

    Xue, Li; Chen, Xiaoyong; Chang, Yanjie; Bieker, James J

    2004-06-01

    Erythroid Krüppel-like factor (EKLF) plays an essential role in enabling beta-globin expression during erythroid ontogeny. It is first expressed in the extraembryonic mesoderm of the yolk sac within the morphologically unique cells that give rise to the blood islands, and then later within the hepatic primordia. The BMP4/Smad pathway plays a critical role in the induction of EKLF, and transient transfection analyses demonstrate that sequences located within less than 1 kb of its transcription initiation site are sufficient for high-level erythroid-specific transcription. We have used transgenic analyses to verify that 950 bp located adjacent to the EKLF start site of transcription is sufficient to generate lacZ expression within the blood islands as well as the fetal liver during embryonic development. Of particular importance are 3 regions, 2 of which overlap endogenous erythroid-specific DNase hypersensitive sites, and 1 of which includes the proximal promoter region. The onset of transgene expression mimics that of endogenous EKLF as it begins by day 7.5 (d7.5) to d8.0. In addition, it exhibits a strict hematopoietic specificity, localized only to these cells and not to the adjacent vasculature at all stages examined. Finally, expression is heterocellular, implying that although these elements are sufficient for tissue-specific expression, they do not shield against the position effects of adjacent chromatin. These analyses demonstrate that a surprisingly small DNA segment contains all the information needed to target a linked gene to the hematopoietic compartment at both early and later stages of development, and may be a useful cassette for this purpose. PMID:14764531

  5. The DNA binding factor Hmg20b is a repressor of erythroid differentiation

    PubMed Central

    Esteghamat, Fatemehsadat; van Dijk, Thamar Bryn; Braun, Harald; Dekker, Sylvia; van der Linden, Reinier; Hou, Jun; Fanis, Pavlos; Demmers, Jeroen; van IJcken, Wilfred; Özgür, Zeliha; Horos, Rastislav; Pourfarzad, Farzin; von Lindern, Marieke; Philipsen, Sjaak

    2011-01-01

    Background In erythroblasts, the CoREST repressor complex is recruited to target promoters by the transcription factor Gfi1b, leading to repression of genes mainly involved in erythroid differentiation. Hmg20b is a subunit of CoREST, but its role in erythropoiesis has not yet been established. Design and Methods To study the role of Hmg20b in erythropoiesis, we performed knockdown experiments in a differentiation-competent mouse fetal liver cell line, and in primary mouse fetal liver cells. The effects on globin gene expression were determined. We used microarrays to investigate global gene expression changes induced by Hmg20b knockdown. Functional analysis was carried out on Hrasls3, an Hmg20b target gene. Results We show that Hmg20b depletion induces spontaneous differentiation. To identify the target genes of Hmg20b, microarray analysis was performed on Hmg20b knockdown cells and controls. In line with its association to the CoREST complex, we found that 85% (527 out of 620) of the deregulated genes are up-regulated when Hmg20b levels are reduced. Among the few down-regulated genes was Gfi1b, a known repressor of erythroid differentiation. Among the consistently up-regulated targets were embryonic β-like globins and the phospholipase HRAS-like suppressor 3 (Hrasls3). We show that Hrasls3 expression is induced during erythroid differentiation and that knockdown of Hrasls3 inhibits terminal differentiation of proerythroblasts. Conclusions We conclude that Hmg20b acts as an inhibitor of erythroid differentiation, through the down-regulation of genes involved in differentiation such as Hrasls3, and activation of repressors of differentiation such as Gfi1b. In addition, Hmg20b suppresses embryonic β-like globins. PMID:21606163

  6. The Effect of Mir-451 Upregulation on Erythroid Lineage Differentiation of Murine Embryonic Stem Cells

    PubMed Central

    Obeidi, Narges; Pourfathollah, Ali Akbar; Soleimani, Masoud; Nikougoftar Zarif, Mahin; Kouhkan, Fatemeh

    2016-01-01

    Objective MicroRNAs (miRNAs) are small endogenous non-coding regulatory RNAs that control mRNAs post-transcriptionally. Several mouse stem cells miRNAs are cloned differentially regulated in different hematopoietic lineages, suggesting their possible role in hematopoietic lineage differentiation. Recent studies have shown that specific miRNAs such as Mir-451 have key roles in erythropoiesis. Materials and Methods In this experimental study, murine embryonic stem cells (mESCs) were infected with lentiviruses containing pCDH-Mir-451. Erythroid differentiation was assessed based on the expression level of transcriptional factors (Gata-1, Klf-1, Epor) and hemoglobin chains (α, β, γ , ε and ζ) genes using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and presence of erythroid surface antigens (TER-119 and CD235a) using flow cytometery. Colony-forming unit (CFU) assay was also on days 14thand 21thafter transduction. Results Mature Mir-451 expression level increased by 3.434-fold relative to the untreated mESCs on day 4 after transduction (P<0.001). Mir-451 up-regulation correlated with the induction of transcriptional factor (Gata-1, Klf-1, Epor) and hemoglobin chain (α, β, γ, ε and ζ) genes in mESCs (P<0.001) and also showed a strong correlation with presence of CD235a and Ter- 119 markers in these cells (13.084and 13.327-fold increse, respectively) (P<0.05). Moreover, mESCs treated with pCDH-Mir-451 showed a significant raise in CFU-erythroid (CFU-E) colonies (5.2-fold) compared with untreated control group (P<0.05). Conclusion Our results showed that Mir-451 up-regulation strongly induces erythroid differentiation and maturation of mESCs. Overexpression of Mir-451 may have the potential to produce artificial red blood cells (RBCs) without the presence of any stimulatory cytokines. PMID:27540521

  7. Reduced DOCK4 expression leads to erythroid dysplasia in myelodysplastic syndromes

    PubMed Central

    Sundaravel, Sriram; Duggan, Ryan; Bhagat, Tushar; Ebenezer, David L.; Liu, Hui; Yu, Yiting; Bartenstein, Matthias; Unnikrishnan, Madhu; Karmakar, Subhradip; Liu, Ting-Chun; Torregroza, Ingrid; Quenon, Thomas; Anastasi, John; McGraw, Kathy L.; Pellagatti, Andrea; Boultwood, Jacqueline; Yajnik, Vijay; Artz, Andrew; Le Beau, Michelle M.; Steidl, Ulrich; List, Alan F.; Evans, Todd; Verma, Amit; Wickrema, Amittha

    2015-01-01

    Anemia is the predominant clinical manifestation of myelodysplastic syndromes (MDS). Loss or deletion of chromosome 7 is commonly seen in MDS and leads to a poor prognosis. However, the identity of functionally relevant, dysplasia-causing, genes on 7q remains unclear. Dedicator of cytokinesis 4 (DOCK4) is a GTPase exchange factor, and its gene maps to the commonly deleted 7q region. We demonstrate that DOCK4 is underexpressed in MDS bone marrow samples and that the reduced expression is associated with decreased overall survival in patients. We show that depletion of DOCK4 levels leads to erythroid cells with dysplastic morphology both in vivo and in vitro. We established a novel single-cell assay to quantify disrupted F-actin filament network in erythroblasts and demonstrate that reduced expression of DOCK4 leads to disruption of the actin filaments, resulting in erythroid dysplasia that phenocopies the red blood cell (RBC) defects seen in samples from MDS patients. Reexpression of DOCK4 in −7q MDS patient erythroblasts resulted in significant erythropoietic improvements. Mechanisms underlying F-actin disruption revealed that DOCK4 knockdown reduces ras-related C3 botulinum toxin substrate 1 (RAC1) GTPase activation, leading to increased phosphorylation of the actin-stabilizing protein ADDUCIN in MDS samples. These data identify DOCK4 as a putative 7q gene whose reduced expression can lead to erythroid dysplasia. PMID:26578796

  8. GATA1 and PU.1 Bind to Ribosomal Protein Genes in Erythroid Cells: Implications for Ribosomopathies

    PubMed Central

    Amanatiadou, Elsa P.; Papadopoulos, Giorgio L.; Strouboulis, John; Vizirianakis, Ioannis S.

    2015-01-01

    The clear connection between ribosome biogenesis dysfunction and specific hematopoiesis-related disorders prompted us to examine the role of critical lineage-specific transcription factors in the transcriptional regulation of ribosomal protein (RP) genes during terminal erythroid differentiation. By applying EMSA and ChIP methodologies in mouse erythroleukemia cells we show that GATA1 and PU.1 bind in vitro and in vivo the proximal promoter region of the RPS19 gene which is frequently mutated in Diamond-Blackfan Anemia. Moreover, ChIPseq data analysis also demonstrates that several RP genes are enriched as potential GATA1 and PU.1 gene targets in mouse and human erythroid cells, with GATA1 binding showing an association with higher ribosomal protein gene expression levels during terminal erythroid differentiation in human and mouse. Our results suggest that RP gene expression and hence balanced ribosome biosynthesis may be specifically and selectively regulated by lineage specific transcription factors during hematopoiesis, a finding which may be clinically relevant to ribosomopathies. PMID:26447946

  9. GATA1 and PU.1 Bind to Ribosomal Protein Genes in Erythroid Cells: Implications for Ribosomopathies.

    PubMed

    Amanatiadou, Elsa P; Papadopoulos, Giorgio L; Strouboulis, John; Vizirianakis, Ioannis S

    2015-01-01

    The clear connection between ribosome biogenesis dysfunction and specific hematopoiesis-related disorders prompted us to examine the role of critical lineage-specific transcription factors in the transcriptional regulation of ribosomal protein (RP) genes during terminal erythroid differentiation. By applying EMSA and ChIP methodologies in mouse erythroleukemia cells we show that GATA1 and PU.1 bind in vitro and in vivo the proximal promoter region of the RPS19 gene which is frequently mutated in Diamond-Blackfan Anemia. Moreover, ChIPseq data analysis also demonstrates that several RP genes are enriched as potential GATA1 and PU.1 gene targets in mouse and human erythroid cells, with GATA1 binding showing an association with higher ribosomal protein gene expression levels during terminal erythroid differentiation in human and mouse. Our results suggest that RP gene expression and hence balanced ribosome biosynthesis may be specifically and selectively regulated by lineage specific transcription factors during hematopoiesis, a finding which may be clinically relevant to ribosomopathies. PMID:26447946

  10. Induction of erythroid differentiation and modulation of gene expression by tiazofurin in K-562 leukemia cells.

    PubMed Central

    Olah, E; Natsumeda, Y; Ikegami, T; Kote, Z; Horanyi, M; Szelenyi, J; Paulik, E; Kremmer, T; Hollan, S R; Sugar, J

    1988-01-01

    Tiazofurin (2-beta-D-ribofuranosyl-4-thiazole-carboxamide; NSC 286193), an antitumor carbon-linked nucleoside that inhibits IMP dehydrogenase (IMP:NAD+ oxidoreductase; EC 1.1.1.205) and depletes guanylate levels, can activate the erythroid differentiation program of K-562 human leukemia cells. Tiazofurin-mediated cell differentiation is a multistep process. The inducer initiates early (less than 6 hr) metabolic changes that precede commitment to differentiation; among these early changes are decreases in IMP dehydrogenase activity and in GTP concentration, as well as alterations in the expression of certain protooncogenes (c-Ki-ras). K-562 cells do express commitment-i.e., cells exhibit differentiation without tiazofurin. Guanosine was effective in preventing the action of tiazofurin, thus providing evidence that the guanine nucleotides are critically involved in tiazofurin-initiated differentiation. Activation of transcription of the erythroid-specific gene that encodes A gamma-globin is a late (48 hr) but striking effect of tiazofurin. Down-regulation of the c-ras gene appears to be part of the complex process associated with tiazofurin-induced erythroid differentiation and relates to the perturbations of GTP metabolism. Images PMID:2901100

  11. FOG-1 and GATA-1 act sequentially to specify definitive megakaryocytic and erythroid progenitors

    PubMed Central

    Mancini, Elena; Sanjuan-Pla, Alejandra; Luciani, Luisa; Moore, Susan; Grover, Amit; Zay, Agnes; Rasmussen, Kasper D; Luc, Sidinh; Bilbao, Daniel; O'Carroll, Donal; Jacobsen, Sten Eirik; Nerlov, Claus

    2012-01-01

    The transcription factors that control lineage specification of haematopoietic stem cells (HSCs) have been well described for the myeloid and lymphoid lineages, whereas transcriptional control of erythroid (E) and megakaryocytic (Mk) fate is less understood. We here use conditional removal of the GATA-1 and FOG-1 transcription factors to identify FOG-1 as required for the formation of all committed Mk- and E-lineage progenitors, whereas GATA-1 was observed to be specifically required for E-lineage commitment. FOG-1-deficient HSCs and preMegEs, the latter normally bipotent for the Mk and E lineages, underwent myeloid transcriptional reprogramming, and formed myeloid, but not erythroid and megakaryocytic cells in vitro. These results identify FOG-1 and GATA-1 as required for formation of bipotent Mk/E progenitors and their E-lineage commitment, respectively, and show that FOG-1 mediates transcriptional Mk/E programming of HSCs as well as their subsequent Mk/E-lineage commitment. Finally, C/EBPs and FOG-1 exhibited transcriptional cross-regulation in early myelo-erythroid progenitors making their functional antagonism a potential mechanism for separation of the myeloid and Mk/E lineages. PMID:22068055

  12. Reduced DOCK4 expression leads to erythroid dysplasia in myelodysplastic syndromes.

    PubMed

    Sundaravel, Sriram; Duggan, Ryan; Bhagat, Tushar; Ebenezer, David L; Liu, Hui; Yu, Yiting; Bartenstein, Matthias; Unnikrishnan, Madhu; Karmakar, Subhradip; Liu, Ting-Chun; Torregroza, Ingrid; Quenon, Thomas; Anastasi, John; McGraw, Kathy L; Pellagatti, Andrea; Boultwood, Jacqueline; Yajnik, Vijay; Artz, Andrew; Le Beau, Michelle M; Steidl, Ulrich; List, Alan F; Evans, Todd; Verma, Amit; Wickrema, Amittha

    2015-11-17

    Anemia is the predominant clinical manifestation of myelodysplastic syndromes (MDS). Loss or deletion of chromosome 7 is commonly seen in MDS and leads to a poor prognosis. However, the identity of functionally relevant, dysplasia-causing, genes on 7q remains unclear. Dedicator of cytokinesis 4 (DOCK4) is a GTPase exchange factor, and its gene maps to the commonly deleted 7q region. We demonstrate that DOCK4 is underexpressed in MDS bone marrow samples and that the reduced expression is associated with decreased overall survival in patients. We show that depletion of DOCK4 levels leads to erythroid cells with dysplastic morphology both in vivo and in vitro. We established a novel single-cell assay to quantify disrupted F-actin filament network in erythroblasts and demonstrate that reduced expression of DOCK4 leads to disruption of the actin filaments, resulting in erythroid dysplasia that phenocopies the red blood cell (RBC) defects seen in samples from MDS patients. Reexpression of DOCK4 in -7q MDS patient erythroblasts resulted in significant erythropoietic improvements. Mechanisms underlying F-actin disruption revealed that DOCK4 knockdown reduces ras-related C3 botulinum toxin substrate 1 (RAC1) GTPase activation, leading to increased phosphorylation of the actin-stabilizing protein ADDUCIN in MDS samples. These data identify DOCK4 as a putative 7q gene whose reduced expression can lead to erythroid dysplasia. PMID:26578796

  13. Effects of p38 MAP kinase inhibitors on the differentiation and maturation of erythroid progenitors.

    PubMed

    Dalmas, Deidre A; Tierney, Lauren A; Zhang, Cindy; Narayanan, Padma K; Boyce, Rogely W; Schwartz, Lester W; Frazier, Kendall S; Scicchitano, Marshall S

    2008-12-01

    In rodents, p38 MAP kinase inhibitors (p38is) induce bone marrow hypocellularity and reduce reticulocyte and erythrocyte counts. To identify target cell populations affected, a differentiating primary liquid erythroid culture system using sca-1(+)cells from mouse bone marrow was developed and challenged with p38is SB-203580, SB-226882, and SB-267030. Drug-related alterations in genes involved at different stages of erythropoiesis, cell-surface antigen expression (CSAE), burst-forming unit erythroid (BFU-E) colony formation, and cellular morphology (CM), growth (CG), and viability were evaluated. CSAE, CM, and decreases in BFU-E formation indicated delayed maturation, while CG and viability were unaffected. Terminal differentiation was delayed until day 14 versus day 7 in controls. CSAE demonstrated higher percentages of sca-1(+)cells after day 2 and reduced percentages of ter119(+) cells after day 7 in all treated cultures. Real-time reverse transcriptase polymerase chain reaction revealed a transient delay in expression of genes involved at early, intermediate, and late stages of erythropoiesis, followed by rebound expression at later time points. Results demonstrate p38is do not irreversibly inhibit erythrogenesis but induce a potency-dependent, transient delay in erythropoietic activity. The delay in activity is suggestive of effects on sca-1(+)bone marrow cells caused by alterations in expression of genes related to erythroid commitment and differentiation resulting in delayed maturation. PMID:19126791

  14. Regulation of GATA factor expression is distinct between erythroid and mast cell lineages.

    PubMed

    Ohmori, Shin'ya; Takai, Jun; Ishijima, Yasushi; Suzuki, Mikiko; Moriguchi, Takashi; Philipsen, Sjaak; Yamamoto, Masayuki; Ohneda, Kinuko

    2012-12-01

    The zinc finger transcription factors GATA1 and GATA2 participate in mast cell development. Although the expression of these factors is regulated in a cell lineage-specific and differentiation stage-specific manner, their regulation during mast cell development has not been clarified. Here, we show that the GATA2 mRNA level was significantly increased while GATA1 was maintained at low levels during the differentiation of mast cells derived from mouse bone marrow (BMMCs). Unlike in erythroid cells, forced expression or small interfering RNA (siRNA)-mediated knockdown of GATA1 rarely affected GATA2 expression, and vice versa, in mast cells, indicating the absence of cross-regulation between Gata1 and Gata2 genes. Chromatin immunoprecipitation assays revealed that both GATA factors bound to most of the conserved GATA sites of Gata1 and Gata2 loci in BMMCs. However, the GATA1 hematopoietic enhancer (G1HE) of the Gata1 gene, which is essential for GATA1 expression in erythroid and megakaryocytic lineages, was bound only weakly by both GATA factors in BMMCs. Furthermore, transgenic-mouse reporter assays revealed that the G1HE is not essential for reporter expression in BMMCs and peritoneal mast cells. Collectively, these results demonstrate that the expression of GATA factors in mast cells is regulated in a manner quite distinct from that in erythroid cells. PMID:22988301

  15. Control of developmentally primed erythroid genes by combinatorial co-repressor actions

    PubMed Central

    Stadhouders, Ralph; Cico, Alba; Stephen, Tharshana; Thongjuea, Supat; Kolovos, Petros; Baymaz, H. Irem; Yu, Xiao; Demmers, Jeroen; Bezstarosti, Karel; Maas, Alex; Barroca, Vilma; Kockx, Christel; Ozgur, Zeliha; van Ijcken, Wilfred; Arcangeli, Marie-Laure; Andrieu-Soler, Charlotte; Lenhard, Boris; Grosveld, Frank; Soler, Eric

    2015-01-01

    How transcription factors (TFs) cooperate within large protein complexes to allow rapid modulation of gene expression during development is still largely unknown. Here we show that the key haematopoietic LIM-domain-binding protein-1 (LDB1) TF complex contains several activator and repressor components that together maintain an erythroid-specific gene expression programme primed for rapid activation until differentiation is induced. A combination of proteomics, functional genomics and in vivo studies presented here identifies known and novel co-repressors, most notably the ETO2 and IRF2BP2 proteins, involved in maintaining this primed state. The ETO2–IRF2BP2 axis, interacting with the NCOR1/SMRT co-repressor complex, suppresses the expression of the vast majority of archetypical erythroid genes and pathways until its decommissioning at the onset of terminal erythroid differentiation. Our experiments demonstrate that multimeric regulatory complexes feature a dynamic interplay between activating and repressing components that determines lineage-specific gene expression and cellular differentiation. PMID:26593974

  16. p73 Plays a Role in Erythroid Differentiation through GATA1 Induction*

    PubMed Central

    Marqués-García, Fernando; Ferrandiz, Nuria; Fernández-Alonso, Rosalía; González-Cano, Laura; Herreros-Villanueva, Marta; Rosa-Garrido, Manuel; Fernández-García, Belén; Vaque, José P.; Marqués, Margarita M.; Alonso, María Eugenia; Segovia, José Carlos; León, Javier; Marín, María C.

    2009-01-01

    The TP73 gene gives rise to transactivation domain-p73 isoforms (TAp73) as well as ΔNp73 variants with a truncated N terminus. Although TAp73α and -β proteins are capable of inducing cell cycle arrest, apoptosis, and differentiation, ΔNp73 acts in many cell types as a dominant-negative repressor of p53 and TAp73. It has been proposed that p73 is involved in myeloid differentiation, and its altered expression is involved in leukemic degeneration. However, there is little evidence as to which p73 variants (TA or ΔN) are expressed during differentiation and whether specific p73 isoforms have the capacity to induce, or hinder, this differentiation in leukemia cells. In this study we identify GATA1 as a direct transcriptional target of TAp73α. Furthermore, TAp73α induces GATA1 activity, and it is required for erythroid differentiation. Additionally, we describe a functional cooperation between TAp73 and ΔNp73 in the context of erythroid differentiation in human myeloid cells, K562 and UT-7. Moreover, the impaired expression of GATA1 and other erythroid genes in the liver of p73KO embryos, together with the moderated anemia observed in p73KO young mice, suggests a physiological role for TP73 in erythropoiesis. PMID:19509292

  17. Simulations towards the achievement of non-inductive current ramp-up and sustainment in the National Spherical Torus Experiment Upgrade

    DOE PAGESBeta

    Poli, F. M.; Andre, R. G.; Bertelli, N.; Gerhardt, S. P.; Mueller, D.; Taylor, G.

    2015-10-30

    One of the goals of the National Spherical Torus Experiment Upgrade (NSTX-U) (Menard et al 2012 Nucl. Fusion 52 083015) is the demonstration of fully non-inductive start-up, current ramp-up and sustainment. This work discusses predictive simulations where the available heating and current drive systems are combined to maximize the non-inductive current and minimize the solenoidal contribution. Radio-frequency waves at harmonics higher than the ion cyclotron resonance (high-harmonic fast waves (HHFW)) and neutral beam injection are used to ramp the plasma current non-inductively starting from an initial Ohmic plasma. An interesting synergy is observed in the simulations between the HHFW andmore » electron cyclotron (EC) wave heating. Furthermore, time-dependent simulations indicate that, depending on the phasing of the HHFW antenna, EC wave heating can significantly increase the effectiveness of the radio-frequency power, by heating the electrons and increasing the current drive efficiency, thus relaxing the requirements on the level of HHFW power that needs to be absorbed in the core plasma to drive the same amount of fast-wave current.« less

  18. Simulations towards the achievement of non-inductive current ramp-up and sustainment in the National Spherical Torus Experiment Upgrade

    SciTech Connect

    Poli, F. M.; Andre, R. G.; Bertelli, N.; Gerhardt, S. P.; Mueller, D.; Taylor, G.

    2015-10-30

    One of the goals of the National Spherical Torus Experiment Upgrade (NSTX-U) (Menard et al 2012 Nucl. Fusion 52 083015) is the demonstration of fully non-inductive start-up, current ramp-up and sustainment. This work discusses predictive simulations where the available heating and current drive systems are combined to maximize the non-inductive current and minimize the solenoidal contribution. Radio-frequency waves at harmonics higher than the ion cyclotron resonance (high-harmonic fast waves (HHFW)) and neutral beam injection are used to ramp the plasma current non-inductively starting from an initial Ohmic plasma. An interesting synergy is observed in the simulations between the HHFW and electron cyclotron (EC) wave heating. Furthermore, time-dependent simulations indicate that, depending on the phasing of the HHFW antenna, EC wave heating can significantly increase the effectiveness of the radio-frequency power, by heating the electrons and increasing the current drive efficiency, thus relaxing the requirements on the level of HHFW power that needs to be absorbed in the core plasma to drive the same amount of fast-wave current.

  19. Simulations towards the achievement of non-inductive current ramp-up and sustainment in the National Spherical Torus Experiment Upgrade

    NASA Astrophysics Data System (ADS)

    Poli, F. M.; Andre, R. G.; Bertelli, N.; Gerhardt, S. P.; Mueller, D.; Taylor, G.

    2015-11-01

    One of the goals of the National Spherical Torus Experiment Upgrade (NSTX-U) (Menard et al 2012 Nucl. Fusion 52 083015) is the demonstration of fully non-inductive start-up, current ramp-up and sustainment. This work discusses predictive simulations where the available heating and current drive systems are combined to maximize the non-inductive current and minimize the solenoidal contribution. Radio-frequency waves at harmonics higher than the ion cyclotron resonance (high-harmonic fast waves (HHFW)) and neutral beam injection are used to ramp the plasma current non-inductively starting from an initial Ohmic plasma. An interesting synergy is observed in the simulations between the HHFW and electron cyclotron (EC) wave heating. Time-dependent simulations indicate that, depending on the phasing of the HHFW antenna, EC wave heating can significantly increase the effectiveness of the radio-frequency power, by heating the electrons and increasing the current drive efficiency, thus relaxing the requirements on the level of HHFW power that needs to be absorbed in the core plasma to drive the same amount of fast-wave current.

  20. Achievement of sustained viral response after switching treatment from pegylated interferon α-2b to α-2a and ribavirin in patients with recurrence of hepatitis C virus genotype 1 infection after liver transplantation: a case report.

    PubMed

    Kawaoka, Tomokazu; Hiraga, Nobuhiko; Takahashi, Shoichi; Takaki, Shintaro; Tsuge, Masataka; Nagaoki, Yuko; Hashimoto, Yoshimasa; Katamura, Yoshio; Miki, Daiki; Hiramatsu, Akira; Waki, Koji; Imamura, Michio; Kawakami, Yoshiiku; Aikata, Hiroshi; Ochi, Hidenori; Tashiro, Hirotaka; Ohdan, Hideki; Chayama, Kazuaki

    2012-01-01

    We report a case in which sustained viral response was achieved after switching treatment from pegylated interferon (PEG-IFN) α-2b to α-2a and ribavirin (RBV) in patients with recurrence of hepatitis C virus (HCV) infection after living donor liver transplantation. The patient was a 62-year-old man with liver cirrhosis due to HCV genotype 1b infection. The patient had 8 amino acid (aa) substitutions in the interferon sensitivity-determining region, and had substitutions for mutant and wild-type at aa70 and aa91, respectively, in the core region. The patient had minor genotype (GG) IL28B single nucleotide polymorphisms (rs8099917). He had initially received interferon α-2b and RBV for 2 years, and later developed hepatocellular carcinoma (HCC). After surgical resection of HCC, he subsequently received PEG-IFN α-2b and RBV for 1.5 years, without undetectable viremia during the treatment course. Due to recurrence of HCC, the patient received a living donor liver transplantation. Later on, hepatitis C relapsed. For the management of relapse, he received another course of PEG-IFN α-2b and RBV. However, breakthrough viremia occurred. PEG-IFN was thus switched from α-2b to α-2a and RBV for another 17 months. The patient eventually achieved a sustained viral response. PMID:21865660

  1. Is Sustainability Sustainable?

    ERIC Educational Resources Information Center

    Bonevac, Daniel

    2010-01-01

    The most important concept in current environmental thinking is "sustainability". Environmental policies, economic policies, development, resource use--all of these things, according to the consensus, ought to be sustainable. But what is sustainability? What is its ethical foundation? There is little consensus about how these questions ought to be…

  2. High baseline interleukine-8 level is an independent risk factor for the achievement of sustained virological response in chronic HCV patients.

    PubMed

    Akbar, Haji; Idrees, Muhammad; Butt, Sadia; Awan, Zunaira; Sabar, Muhammd Farooq; Rehaman, Irshad ur; Hussain, Abrar; Saleem, Sana

    2011-08-01

    Hepatitis C virus (HCV), a major cause of liver disease throughout the world, is difficult to treat with interferon (IFN) (and various formulations and combinations thereof) being the only approved molecule available. It has been investigated recently that proinflammatory chemokine interleukin-8 (IL-8) induced by HCV partially inhibits the antiviral IFN-α therapy. Therefore, the current study was aimed to prospectively utilize the baseline IL-8 levels in the HCV infected serum and predicts its role in sustained virological response (SVR) to IFN-α+ribavirin therapy, in chronic HCV patients in Pakistan. One hundred and ten hepatitis C patients without any other infections underwent IFN-α+ribavirin combination treatment. Baseline IL-8 levels were determined before starting of the therapy for all these patients. Fifteen normal volunteers negative for HCV were kept as control. The baseline IL-8 levels were found significantly higher in all HCV positive patients as compared to normal healthy volunteers (1083.54 ± 85.72 pg/ml versus 6.99 ± 1.05 pg/ml [mean ± SEM], p<0.01) and were also significantly higher in non-responders than responders (p<0.05). Comparatively higher mean baseline IL-8 levels were observed in non-responders (2442.02 ± 159.92 pg/ml), than late (1009.31 ± 45.31) and rapid (540.91 ± 27.06 pg/ml) responders. Significant relation was observed between baseline IL-8 level and response to IFN therapy (p<0.01). Results of this study suggest that increased levels of IL-8 in HCV infection might be involved in pathogenesis, persistence and resistance to IFN-α+ribavirin combination therapy. PMID:21554996

  3. PPAR-α and glucocorticoid receptor synergize to promote erythroid progenitor self-renewal.

    PubMed

    Lee, Hsiang-Ying; Gao, Xiaofei; Barrasa, M Inmaculada; Li, Hu; Elmes, Russell R; Peters, Luanne L; Lodish, Harvey F

    2015-06-25

    Many acute and chronic anaemias, including haemolysis, sepsis and genetic bone marrow failure diseases such as Diamond-Blackfan anaemia, are not treatable with erythropoietin (Epo), because the colony-forming unit erythroid progenitors (CFU-Es) that respond to Epo are either too few in number or are not sensitive enough to Epo to maintain sufficient red blood cell production. Treatment of these anaemias requires a drug that acts at an earlier stage of red cell formation and enhances the formation of Epo-sensitive CFU-E progenitors. Recently, we showed that glucocorticoids specifically stimulate self-renewal of an early erythroid progenitor, burst-forming unit erythroid (BFU-E), and increase the production of terminally differentiated erythroid cells. Here we show that activation of the peroxisome proliferator-activated receptor α (PPAR-α) by the PPAR-α agonists GW7647 and fenofibrate synergizes with the glucocorticoid receptor (GR) to promote BFU-E self-renewal. Over time these agonists greatly increase production of mature red blood cells in cultures of both mouse fetal liver BFU-Es and mobilized human adult CD34(+) peripheral blood progenitors, with a new and effective culture system being used for the human cells that generates normal enucleated reticulocytes. Although Ppara(-/-) mice show no haematological difference from wild-type mice in both normal and phenylhydrazine (PHZ)-induced stress erythropoiesis, PPAR-α agonists facilitate recovery of wild-type but not Ppara(-/-) mice from PHZ-induced acute haemolytic anaemia. We also show that PPAR-α alleviates anaemia in a mouse model of chronic anaemia. Finally, both in control and corticosteroid-treated BFU-E cells, PPAR-α co-occupies many chromatin sites with GR; when activated by PPAR-α agonists, additional PPAR-α is recruited to GR-adjacent sites and presumably facilitates GR-dependent BFU-E self-renewal. Our discovery of the role of PPAR-α agonists in stimulating self-renewal of early erythroid

  4. PPARα and glucocorticoid receptor synergize to promote erythroid progenitor self-renewal

    PubMed Central

    Lee, Hsiang-Ying; Gao, Xiaofei; Barrasa, M. Inmaculada; Li, Hu; Elmes, Russell R.; Peters, Luanne L.; Lodish, Harvey F.

    2015-01-01

    Summary Many acute and chronic anemias, including hemolysis, sepsis, and genetic bone marrow failure diseases such as Diamond-Blackfan Anemia (DBA), are not treatable with erythropoietin (Epo), because the colony-forming unit erythroid progenitors (CFU-Es) that respond to Epo are either too few in number or are not sensitive enough to Epo to maintain sufficient red blood cell production 1,2,3–5,6,7,8,9. Treatment of these anemias requires a drug that acts at an earlier stage of red cell formation and enhances the formation of Epo-sensitive CFU-E progenitors. Recently we showed that glucocorticoids specifically stimulate self-renewal of the early erythroid progenitor, the burst-forming unit erythroid (BFU-E), and increase the production of terminally differentiated erythroid cells 10,11. Here we demonstrate that activation of the peroxisome proliferator-activated receptor alpha (PPARα) by PPARα agonists, GW7647 and fenofibrate, synergizes with glucocorticoid receptor (GR) to promote BFU-E self-renewal. Over time these agonists greatly increase production of mature red blood cells in cultures both of mouse fetal liver BFU-Es and of mobilized human adult CD34+ peripheral blood progenitors, the latter employing a new and effective culture system that generates normal enucleated reticulocytes. While PPARα−/− mice show no hematological difference from wild-type mice in both normal and phenylhydrazine (PHZ)-induced stress erythropoiesis, PPARα agonists facilitate recovery of wild-type mice, but not PPARα−/− mice, from PHZ-induced acute hemolytic anemia. We also showed that PPARα alleviates anemia in a mouse model of chronic anemia. Finally, both in control and corticosteroid-treated BFU-E cells PPARα co-occupies many chromatin sites with GR; when activated by PPARα agonists, additional PPARα is recruited to GR-adjacent sites and presumably facilitates GR-dependent BFU-E self-renewal. Our discovery of the role of PPARα agonists in stimulating self

  5. Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability?

    PubMed

    Ong, Wee-Jun; Tan, Lling-Lling; Ng, Yun Hau; Yong, Siek-Ting; Chai, Siang-Piao

    2016-06-22

    at the forefront of this research platform. It is anticipated that this review can stimulate a new research doorway to facilitate the next generation of g-C3N4-based photocatalysts with ameliorated performances by harnessing the outstanding structural, electronic, and optical properties for the development of a sustainable future without environmental detriment. PMID:27199146

  6. Incidence and predictors of cardiovascular disease, chronic kidney disease, and diabetes in HIV/HCV-coinfected patients who achieved sustained virological response.

    PubMed

    Leone, S; Prosperi, M; Costarelli, S; Nasta, P; Maggiolo, F; Di Giambenedetto, S; Saracino, A; Di Pietro, M; Gori, A

    2016-09-01

    Data on the effects of sustained virologic response (SVR) to hepatitis C virus (HCV) therapy on the outcome of extrahepatic complications are scarce. We conducted this study to assess the impact of SVR on the occurrence of chronic kidney disease (CKD), diabetes mellitus (DM), and cardiovascular disease (CVD) in a cohort of human immunodeficiency virus (HIV)-infected patients. We analyzed coinfected HIV/HCV patients in the Management of Standardized Evaluation of Retroviral HIV Infection (MASTER) cohort. Only event-free patients with a serum HCV-RNA determination at baseline were included. Patients were divided into four groups: INF-exposed with SVR; INF-exposed without SVR; spontaneous HCV clearance; untreated viremic patients. We estimated the incidence of extrahepatic complications and employed Kaplan-Meier curves and Cox regression to assess the association of SVR/INF strata adjusted for a series of confounders. Data from 1676 patients were analyzed (20.29 % started an INF-based regimen). Overall, the incidence of CKD, DM, CVD, and death was 5.32 [95 % confidence interval (CI) 3.99-6.98], 10.13 (95 % CI 8.20-12.37), 6.79 (95 % CI 5.26-8.65), and 13.49 (95 % CI 11.29-16.0) per 1000 person-years of follow-up, respectively. In the Cox model for treated patients, SVR was not associated with a lower risk of CKD, DM, CVD, and death compared to non-SVR. Cirrhosis was significantly associated with a higher risk of CKD [hazard ratio (HR) 2.13; 95 % CI 1.06-4.31], DM (HR 3.48; 95 % CI 2.18-5.57), and death (HR 6.18; 95 % CI 4.1-9.31), but not of CVD (HR 1.14; 95 % CI 0.57-2.3). There are still many unknowns regarding the impact of SVR on the occurrence of extrahepatic complications in coinfected HIV/HCV patients. Further investigations are needed in order to elucidate the role of SVR as an independent prognostic factor for extrahepatic events. PMID:27272121

  7. Risk of Late Relapse or Reinfection With Hepatitis C Virus After Achieving a Sustained Virological Response: A Systematic Review and Meta-analysis

    PubMed Central

    Simmons, Bryony; Saleem, Jawaad; Hill, Andrew; Riley, Richard D.; Cooke, Graham S.

    2016-01-01

    Background. Treatment for hepatitis C virus (HCV) can lead to sustained virological response (SVR) in over 90% of people. Subsequent recurrence of HCV, either from late relapse or reinfection, reverses the beneficial effects of SVR. Methods. A search identified studies analysing HCV recurrence post-SVR. The recurrence rate for each study was calculated using events/person years of follow-up (PYFU). Results were pooled using a random-effects model and used to calculate 5-year recurrence risk. Three patient groups were analysed: (1) Mono-HCV infected “low-risk” patients; (2) Mono-HCV infected “high-risk” patients (injecting drug users or prisoners); (3) human immunodeficiency virus (HIV)/HCV coinfected patients. Recurrence was defined as confirmed HCV RNA detectability post-SVR. Results. In the 43 studies of HCV mono-infected “low-risk” patients (n = 7969) the pooled recurrence rate was 1.85/1000 PYFU (95% confidence interval [CI], .71–3.35; I2 = 73%) leading to a summary 5-year recurrence risk of 0.95% (95% CI, .35%–1.69%). For the 14 studies of HCV monoinfected “high-risk” patients (n = 771) the pooled recurrence rate was 22.32/1000 PYFU (95% CI, 13.07–33.46; I2 = 27%) leading to a summary 5-year risk of 10.67% (95% CI, 6.38%–15.66%). For the 4 studies of HIV/HCV coinfected patients the pooled recurrence rate was 32.02/1000 PYFU (95% CI, .00–123.49; I2 = 96%) leading to a summary 5-year risk of 15.02% (95% CI, .00%–48.26%). The higher pooled estimates of recurrence in the high-risk and coinfected cohorts were driven by an increase in reinfection rather than late relapse. Conclusions. SVR appears durable in the majority of patients at 5 years post-treatment. The large difference in 5 year event rate by risk group is driven mainly by an increased reinfection risk. PMID:26787172

  8. Kit transduced signals counteract erythroid maturation by MAPK-dependent modulation of erythropoietin signaling and apoptosis induction in mouse fetal liver.

    PubMed

    Haas, N; Riedt, T; Labbaf, Z; Baßler, K; Gergis, D; Fröhlich, H; Gütgemann, I; Janzen, V; Schorle, H

    2015-05-01

    Signaling by the stem cell factor receptor Kit in hematopoietic stem and progenitor cells is functionally associated with the regulation of cellular proliferation, differentiation and survival. Expression of the receptor is downregulated upon terminal differentiation in most lineages, including red blood cell terminal maturation, suggesting that omission of Kit transduced signals is a prerequisite for the differentiation process to occur. However, the molecular mechanisms by which Kit signaling preserves the undifferentiated state of progenitor cells are not yet characterized in detail. In this study, we generated a mouse model for inducible expression of a Kit receptor carrying an activating mutation and studied its effects on fetal liver hematopoiesis. We found that sustained Kit signaling leads to expansion of erythroid precursors and interferes with terminal maturation beyond the erythroblast stage. Primary KIT(D816V) erythroblasts stimulated to differentiate fail to exit cell cycle and show elevated rates of apoptosis because of insufficient induction of survival factors. They further retain expression of progenitor cell associated factors c-Myc, c-Myb and GATA-2 and inefficiently upregulate erythroid transcription factors GATA-1, Klf1 and Tal1. In KIT(D816V) erythroblasts we found constitutive activation of the mitogen-activated protein kinase (MAPK) pathway, elevated expression of the src kinase family member Lyn and impaired Akt activation in response to erythropoietin. We demonstrate that the block in differentiation is partially rescued by MAPK inhibition, and completely rescued by the multikinase inhibitor Dasatinib. These results show that a crosstalk between Kit and erythropoietin receptor signaling cascades exists and that continuous Kit signaling, partly mediated by the MAPK pathway, interferes with this crosstalk. PMID:25323585

  9. Disruption of nuclear factor (erythroid-derived-2)-like 2 antioxidant signaling: a mechanism for impaired activation of stem cells and delayed regeneration of skeletal muscle.

    PubMed

    Shelar, Sandeep Balu; Narasimhan, Madhusudhanan; Shanmugam, Gobinath; Litovsky, Silvio Hector; Gounder, Sellamuthu S; Karan, Goutam; Arulvasu, Cinnasamy; Kensler, Thomas W; Hoidal, John R; Darley-Usmar, Victor M; Rajasekaran, Namakkal S

    2016-05-01

    Recently we have reported that age-dependent decline in antioxidant levels accelerated apoptosis and skeletal muscle degeneration. Here, we demonstrate genetic ablation of the master cytoprotective transcription factor, nuclear factor (erythroid-derived-2)-like 2 (Nrf2), aggravates cardiotoxin (CTX)-induced tibialis anterior (TA) muscle damage. Disruption of Nrf2 signaling sustained the CTX-induced burden of reactive oxygen species together with compromised expression of antioxidant genes and proteins. Transcript/protein expression of phenotypic markers of muscle differentiation, namely paired box 7 (satellite cell) and early myogenic differentiation and terminal differentiation (myogenin and myosin heavy chain 2) were increased on d 2 and 4 postinjury but later returned to baseline levels on d 8 and 15 in wild-type (WT) mice. In contrast, these responses were persistently augmented in Nrf2-null mice suggesting that regulation of the regeneration-related signaling mechanisms require Nrf2 for normal functioning. Furthermore, Nrf2-null mice displayed slower regeneration marked by dysregulation of embryonic myosin heavy chain temporal expression. Histologic observations illustrated that Nrf2-null mice displayed smaller, immature TA muscle fibers compared with WT counterparts on d 15 after CTX injury. Improvement in TA muscle morphology and gain in muscle mass evident in the WT mice was not noticeable in the Nrf2-null animals. Taken together these data show that the satellite cell activation, proliferation, and differentiation requires a functional Nrf2 system for effective healing following injury.-Shelar, S. B., Narasimhan, M., Shanmugam, G., Litovsky, S. H., Gounder, S. S., Karan, G., Arulvasu, C., Kensler, T. W., Hoidal, J. R., Darley-Usmar, V. M., Rajasekaran, N. S. Disruption of nuclear factor (erythroid-derived-2)-like 2 antioxidant signaling: a mechanism for impaired activation of stem cells and delayed regeneration of skeletal muscle. PMID:26839378

  10. Kit transduced signals counteract erythroid maturation by MAPK-dependent modulation of erythropoietin signaling and apoptosis induction in mouse fetal liver

    PubMed Central

    Haas, N; Riedt, T; Labbaf, Z; Baßler, K; Gergis, D; Fröhlich, H; Gütgemann, I; Janzen, V; Schorle, H

    2015-01-01

    Signaling by the stem cell factor receptor Kit in hematopoietic stem and progenitor cells is functionally associated with the regulation of cellular proliferation, differentiation and survival. Expression of the receptor is downregulated upon terminal differentiation in most lineages, including red blood cell terminal maturation, suggesting that omission of Kit transduced signals is a prerequisite for the differentiation process to occur. However, the molecular mechanisms by which Kit signaling preserves the undifferentiated state of progenitor cells are not yet characterized in detail. In this study, we generated a mouse model for inducible expression of a Kit receptor carrying an activating mutation and studied its effects on fetal liver hematopoiesis. We found that sustained Kit signaling leads to expansion of erythroid precursors and interferes with terminal maturation beyond the erythroblast stage. Primary KITD816V erythroblasts stimulated to differentiate fail to exit cell cycle and show elevated rates of apoptosis because of insufficient induction of survival factors. They further retain expression of progenitor cell associated factors c-Myc, c-Myb and GATA-2 and inefficiently upregulate erythroid transcription factors GATA-1, Klf1 and Tal1. In KITD816V erythroblasts we found constitutive activation of the mitogen-activated protein kinase (MAPK) pathway, elevated expression of the src kinase family member Lyn and impaired Akt activation in response to erythropoietin. We demonstrate that the block in differentiation is partially rescued by MAPK inhibition, and completely rescued by the multikinase inhibitor Dasatinib. These results show that a crosstalk between Kit and erythropoietin receptor signaling cascades exists and that continuous Kit signaling, partly mediated by the MAPK pathway, interferes with this crosstalk. PMID:25323585

  11. Erythroid-specific activity of the glycophorin B promoter requires GATA-1 mediated displacement of a repressor.

    PubMed Central

    Rahuel, C; Vinit, M A; Lemarchandel, V; Cartron, J P; Roméo, P H

    1992-01-01

    We have performed a detailed analysis of the cis-acting sequences involved in the erythroid-specific expression of the human glycophorin B (GPB) promoter and found that this promoter could be divided into two regions. The proximal region, -1 to -60, contains a GATA binding sequence around -37 and an SP1 binding sequence around -50. This region is active in erythroid and non-erythroid cells. The distal region, -60 to -95, contains two overlapping protein binding sites around -75, one for hGATA-1 and one for ubiquitous proteins. This distal region completely represses the activity of the proximal promoter in non-erythroid cells and defines the -95 GPB construct as a GPB promoter that displays erythroid specificity. Using site directed mutagenesis, we show that the -37 GATA and the -50 SP1 binding sites are necessary for efficient activity of the -95 GPB construct. Mutations that impair the -75 GATA-1 binding result in extinction of the -95 GPB construct activity if the -75 ubiquitous binding site is not altered, or in loss of erythroid specificity if the -75 ubiquitous binding site is also mutated. Using a cotransfection assay, we found that hGATA-1 can efficiently activate transcription of the -95 GPB construct in non-erythroid cells. This transactivation is abolished by mutations that impair either the -37 GATA-1 or the -50 SP1 binding. Mutations that impair the -75 GATA-1 binding and still allow the -75 ubiquitous binding also abolish the transactivation of the -95 GPB construct, indicating that hGATA-1 can remove repression of the GPB promoter by displacement of the ubiquitous proteins.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:1396593

  12. ZFP36L2 is required for self-renewal of early burst-forming unit erythroid progenitors.

    PubMed

    Zhang, Lingbo; Prak, Lina; Rayon-Estrada, Violeta; Thiru, Prathapan; Flygare, Johan; Lim, Bing; Lodish, Harvey F

    2013-07-01

    Stem cells and progenitors in many lineages undergo self-renewing divisions, but the extracellular and intracellular proteins that regulate this process are largely unknown. Glucocorticoids stimulate red blood cell formation by promoting self-renewal of early burst-forming unit-erythroid (BFU-E) progenitors. Here we show that the RNA-binding protein ZFP36L2 is a transcriptional target of the glucocorticoid receptor (GR) in BFU-Es and is required for BFU-E self-renewal. ZFP36L2 is normally downregulated during erythroid differentiation from the BFU-E stage, but its expression is maintained by all tested GR agonists that stimulate BFU-E self-renewal, and the GR binds to several potential enhancer regions of ZFP36L2. Knockdown of ZFP36L2 in cultured BFU-E cells did not affect the rate of cell division but disrupted glucocorticoid-induced BFU-E self-renewal, and knockdown of ZFP36L2 in transplanted erythroid progenitors prevented expansion of erythroid lineage progenitors normally seen following induction of anaemia by phenylhydrazine treatment. ZFP36L2 preferentially binds to messenger RNAs that are induced or maintained at high expression levels during terminal erythroid differentiation and negatively regulates their expression levels. ZFP36L2 therefore functions as part of a molecular switch promoting BFU-E self-renewal and a subsequent increase in the total numbers of colony-forming unit-erythroid (CFU-E) progenitors and erythroid cells that are generated. PMID:23748442

  13. Inhibitory effect of the substance P and its derivative on erythropoietin-independent growth of erythroid progenitors in polycythemia vera.

    PubMed

    Le Gall, Christelle; Ianotto, Jean-Christophe; Hardy, Elisabeth; Ugo, Valérie; Eveillard, Jean-Richard; Ngo-Sack, Françoise; Bourquard, Pascal; Morice, Patrick; Berthou, Christian

    2008-05-01

    Regulation of normal hematopoiesis by neuropeptide substance P (SP) and its amino terminal fragment, SP(1-4), has been reported. Endogenous erythroid colony (EEC) formation without erythropoietin is characteristic of polycythemia vera (PV), a chronic myeloproliferative disorder. We investigated the effect(s) of SP and SP(1-4) on EEC formation from PV BM mononuclear cells (BMMCs) and purified CD36+ erythroid progenitors. We found a potent in vitro inhibitory effect of SP and SP(1-4) on PV EEC formation for both BMMCs and CD36+ erythroid progenitors. The influence of SP and SP(1-4) on PV progenitor erythroid differentiation and cell viability was also investigated, and the impact of neurokinin receptors and G proteins in the inhibition were analyzed by quantitative PCR and with specific inhibitors. This progenitor inhibition was: (1) not mediated by accessory cells; (2) characterized by an increase in cell death and inhibition of the EPOindependent terminal erythroid differentiation; and (3) not mediated by the same neurokinin receptor. NK-1R and NK-2R antagonists completely abrogated the SP inhibitory effect but not SP(1-4)-induced inhibition. Furthermore, the truncated form of the NK-1R was predominant over the full-length mRNA and could mediated the SP inhibitory effect on PV CD36+ erythroid progenitors. Different G proteins were also implicated according to the erythroid differentiation stage of the PV cells. The observation of an inhibitory effect of SP and its related peptide, SP(1-4), on PV EEC formation at physiological concentrations (10-8M) suggests that neuropeptides represent a way to downregulate pathologic expansion of PV progenitors. PMID:17980427

  14. Role of PI3K, MAPK/ERK1/2, and p38 in implementation of the proliferative and differentiation potential of erythroid progenitors after blood loss.

    PubMed

    Dygai, A M; Zhdanov, V V; Miroshnichenko, L A; Udut, E V; Zyuz'kov, G N; Simanina, E V; Sherstoboev, E Yu; Chaikovskii, A V; Stavrova, L A; Burmina, Ya V; Khrichkova, T Yu; Reichart, D V; Goldberg, V E

    2015-02-01

    The involvement of PI3K, ERK and p38-dependent signaling system in the regulation of functional activity of erythroid precursors after blood loss (30% of circulating volume) was studied. We demonstrated the important role of PI3K and p38 in the suppression of differentiation of erythroid precursors the contribution of p38 to stimulation of mitotic activity of erythroid CFU, which maintains the growth potential of the precursors at the optimal physiological level. The classical MAPK/ERK-kinase pathway does not determine the proliferative and differentiation status of erythroid CFU. PMID:25711660

  15. Mathematical modeling reveals differential effects of erythropoietin on proliferation and lineage commitment of human hematopoietic progenitors in early erythroid culture

    PubMed Central

    Ward, Daniel; Carter, Deborah; Homer, Martin; Marucci, Lucia; Gampel, Alexandra

    2016-01-01

    Erythropoietin is essential for the production of mature erythroid cells, promoting both proliferation and survival. Whether erythropoietin and other cytokines can influence lineage commitment of hematopoietic stem and progenitor cells is of significant interest. To study lineage restriction of the common myeloid progenitor to the megakaryocyte/erythroid progenitor of peripheral blood CD34+ cells, we have shown that the cell surface protein CD36 identifies the earliest lineage restricted megakaryocyte/erythroid progenitor. Using this marker and carboxyfluorescein succinimidyl ester to track cell divisions in vitro, we have developed a mathematical model that accurately predicts population dynamics of erythroid culture. Parameters derived from the modeling of cultures without added erythropoietin indicate that the rate of lineage restriction is not affected by erythropoietin. By contrast, megakaryocyte/erythroid progenitor proliferation is sensitive to erythropoietin from the time that CD36 first appears at the cell surface. These results shed new light on the role of erythropoietin in erythropoiesis and provide a powerful tool for further study of hematopoietic progenitor lineage restriction and erythropoiesis. PMID:26589912

  16. Mathematical modeling reveals differential effects of erythropoietin on proliferation and lineage commitment of human hematopoietic progenitors in early erythroid culture.

    PubMed

    Ward, Daniel; Carter, Deborah; Homer, Martin; Marucci, Lucia; Gampel, Alexandra

    2016-03-01

    Erythropoietin is essential for the production of mature erythroid cells, promoting both proliferation and survival. Whether erythropoietin and other cytokines can influence lineage commitment of hematopoietic stem and progenitor cells is of significant interest. To study lineage restriction of the common myeloid progenitor to the megakaryocyte/erythroid progenitor of peripheral blood CD34(+) cells, we have shown that the cell surface protein CD36 identifies the earliest lineage restricted megakaryocyte/erythroid progenitor. Using this marker and carboxyfluorescein succinimidyl ester to track cell divisions in vitro, we have developed a mathematical model that accurately predicts population dynamics of erythroid culture. Parameters derived from the modeling of cultures without added erythropoietin indicate that the rate of lineage restriction is not affected by erythropoietin. By contrast, megakaryocyte/erythroid progenitor proliferation is sensitive to erythropoietin from the time that CD36 first appears at the cell surface. These results shed new light on the role of erythropoietin in erythropoiesis and provide a powerful tool for further study of hematopoietic progenitor lineage restriction and erythropoiesis. PMID:26589912

  17. Induction of foetal haemoglobin synthesis in erythroid progenitor stem cells: mediated by water-soluble components of Terminalia catappa.

    PubMed

    Aimola, I A; Inuwa, H M; Nok, A J; Mamman, A I

    2014-06-01

    Current novel therapeutic agents for the treatment of sickle cell anaemia (SCA) focus on increasing foetal haemoglobin (HbF) levels in SCA patients. Unfortunately, the only approved HbF-inducing agent, hydroxyurea, has long-term unpredictable side effects. Studies have shown the potential of plant compounds to modulate HbF synthesis in primary erythroid progenitor stem cells. We isolated a novel HbF-inducing Terminalia catappa distilled water active fraction (TCDWF) from Terminalia catappa leaves that induced the commitment of erythroid progenitor stem cells to the erythroid lineage and relatively higher HbF synthesis of 9.2- and 6.8-fold increases in both erythropoietin (EPO)-independent and EPO-dependent progenitor stem cells respectively. TCDWF was differentially cytotoxic to EPO-dependent and EPO-independent erythroid progenitor stem cell cultures as revealed by lactate dehydrogenase release from the cells. TCDWF demonstrated a protective effect on EPO-dependent and not EPO-independent progenitor cells. TCDWF induced a modest increase in caspase 3 activity in EPO-independent erythroid progenitor stem cell cultures compared with a significantly higher (P˂0.05) caspase 3 activity in EPO-dependent ones. The results demonstrate that TCDWF may hold promising HbF-inducing compounds, which work synergistically, and suggest a dual modulatory effect on erythropoiesis inherent in this active fraction. PMID:24470326

  18. Rps14 haploinsufficiency causes a block in erythroid differentiation mediated by S100A8 and S100A9.

    PubMed

    Schneider, Rebekka K; Schenone, Monica; Ferreira, Monica Ventura; Kramann, Rafael; Joyce, Cailin E; Hartigan, Christina; Beier, Fabian; Brümmendorf, Tim H; Germing, Ulrich; Platzbecker, Uwe; Büsche, Guntram; Knüchel, Ruth; Chen, Michelle C; Waters, Christopher S; Chen, Edwin; Chu, Lisa P; Novina, Carl D; Lindsley, R Coleman; Carr, Steven A; Ebert, Benjamin L

    2016-03-01

    Impaired erythropoiesis in the deletion 5q (del(5q)) subtype of myelodysplastic syndrome (MDS) has been linked to heterozygous deletion of RPS14, which encodes the ribosomal protein small subunit 14. We generated mice with conditional inactivation of Rps14 and demonstrated an erythroid differentiation defect that is dependent on the tumor suppressor protein p53 (encoded by Trp53 in mice) and is characterized by apoptosis at the transition from polychromatic to orthochromatic erythroblasts. This defect resulted in age-dependent progressive anemia, megakaryocyte dysplasia and loss of hematopoietic stem cell (HSC) quiescence. As assessed by quantitative proteomics, mutant erythroblasts expressed higher levels of proteins involved in innate immune signaling, notably the heterodimeric S100 calcium-binding proteins S100a8 and S100a9. S100a8--whose expression was increased in mutant erythroblasts, monocytes and macrophages--is functionally involved in the erythroid defect caused by the Rps14 deletion, as addition of recombinant S100a8 was sufficient to induce a differentiation defect in wild-type erythroid cells, and genetic inactivation of S100a8 expression rescued the erythroid differentiation defect of Rps14-haploinsufficient HSCs. Our data link Rps14 haploinsufficiency in del(5q) MDS to activation of the innate immune system and induction of S100A8-S100A9 expression, leading to a p53-dependent erythroid differentiation defect. PMID:26878232

  19. Glucocorticoid receptor mediates the expansion of splenic late erythroid progenitors during chronic psychological stress.

    PubMed

    Vignjevic, S; Budec, M; Markovic, D; Dikic, D; Mitrovic, O; Diklic, M; Suboticki, T; Cokic, V; Jovcic, G

    2015-02-01

    Stress evokes an integrated neuroendocrine response perturbing the homeostasis of different physiological systems. In contrast to well established physiologica linteractions between neuroendocrine and immune systems during chronic stress, there has been relatively little information on the effects of psychological stress on erythroid cells. Since stress-induced erythropoiesis occurs predominantly in the spleen, in the current study, we investigated the influence of chronic psychological stress on splenic erythroid progenitors and examined a role of glucocorticoid receptor (GR) in observed effect using a mouse model of restraint. The adult male mice were subjected to 2 hours daily restraint stress for 7 or 14 consecutive days and the role of GR in erythropoietic response to stress was assessed by pretreatment of mice with GR antagonist mifepristone 60 min prior to restraint. The results showed that chronic restraint stress induced an increase in spleen weight as well as in the cellularity of red pulp, as compared to controls. Furthermore, 7 and 14 days of restraint stress resulted in markedly increased number of both splenic early (BFU-E) and late (CFU-E) erythroid progenitors. Blockade of GR with mifepristone did not affect the number of BFU-E in stressed mice, but it completely abolished the effect of repeated psychological stress on CFU-E cells. Additionally, plasma corticosterone concentration was enhanced whereas the GR expression was significantly decreased within splenic red pulp after one and two weeks of stress exposure. Obtained findings suggest for the first time an indispensable role for GR in the expansion of CFU-E progenitors in the spleen under conditions of chronic psychological stress. PMID:25716969

  20. Gamma-interferon alters globin gene expression in neonatal and adult erythroid cells

    SciTech Connect

    Miller, B.A.; Perrine, S.P.; Antognetti, G.; Perlmutter, D.H.; Emerson, S.G.; Sieff, C.; Faller, D.V.

    1987-06-01

    The effect of gamma-interferon on fetal hemoglobin synthesis by purified cord blood, fetal liver, and adult bone marrow erythroid progenitors was studied with a radioligand assay to measure hemoglobin production by BFU-E-derived erythroblasts. Coculture with recombinant gamma-interferon resulted in a significant and dose-dependent decrease in fetal hemoglobin production by neonatal and adult, but not fetal, BFU-E-derived erythroblasts. Accumulation of fetal hemoglobin by cord blood BFU-E-derived erythroblasts decreased up to 38.1% of control cultures (erythropoietin only). Synthesis of both G gamma/A gamma globin was decreased, since the G gamma/A gamma ratio was unchanged. Picograms fetal hemoglobin per cell was decreased by gamma-interferon addition, but picograms total hemoglobin was unchanged, demonstrating that a reciprocal increase in beta-globin production occurred in cultures treated with gamma-interferon. No toxic effect of gamma-interferon on colony growth was noted. The addition of gamma-interferon to cultures resulted in a decrease in the percentage of HbF produced by adult BFU-E-derived cells to 45.6% of control. Fetal hemoglobin production by cord blood, fetal liver, and adult bone marrow erythroid progenitors, was not significantly affected by the addition of recombinant GM-CSF, recombinant interleukin 1 (IL-1), recombinant IL-2, or recombinant alpha-interferon. Although fetal progenitor cells appear unable to alter their fetal hemoglobin program in response to any of the growth factors added here, the interaction of neonatal and adult erythroid progenitors with gamma-interferon results in an altered expression of globin genes.

  1. Fast apoptosis and erythroid differentiation induced by imatinib mesylate in JURL-MK1 cells.

    PubMed

    Kuzelová, Katerina; Grebenová, Dana; Marinov, Iuri; Hrkal, Zbynek

    2005-05-15

    We compare the effects of Imatinib mesylate (Glivec) on chronic myeloid leukemia derived cell lines K562 and JURL-MK1. In both cell lines, the cell cycle arrests in G(1)/G(0) phase within 24 h after the addition of 1 microM Imatinib. This is followed by a decrease of Ki-67 expression and the induction of apoptosis. In JURL-MK1 cells, the apoptosis is faster in comparison with K562 cells: the caspase-3 activity reaches the peak value (20 to 30 fold of the control) after about 40 h and the apoptosis proceeds to its culmination point, the DNA fragmentation, within 48 h following 1 microM Imatinib addition. Unlike K562 cells, JURL-MK1 cells possess a probably functional p53 protein inducible by TPA (tetradecanoyl phorbol acetate) or UV-B irradiation. However, no increase in p53 expression was observed in Imatinib-treated JURL-MK1 cells indicating that the difference in the apoptosis rate between the two cell lines is not due to the lack of p53 in K562 cells. Imatinib also triggers erythroid differentiation both in JURL-MK1 and K562 cells. Glycophorin A expression occurred simultaneously with the apoptosis, even at the single cell level. In K562 cells, but not in JURL-MK1 cells, the differentiation process involved increased hemoglobin synthesis. However, during spontaneous evolution of JURL-MK1 cells in culture, the effects produced by Imatinib progressively changed from the fast apoptosis to the more complete erythroid differentiation. We suggest that the apoptosis and the erythroid differentiation are parallel effects of Imatinib and their relative contributions, kinetics and completeness are related to the differentiation stage of the treated cells. PMID:15770664

  2. Ultrastructural studies on erythropoiesis in the avian thymus. II. A stereological analysis of the lymphoid and erythroid cells.

    PubMed

    Kendall, M D

    1979-06-01

    The cortex of enlarging thymic lobes from adult haemorrhaged Quelea quelea were found to be similar to those of wild birds where the thymic enlargement was occurring naturally. A detailed stereological analysis of cells broadly designated as lymphoid, and the construction of models to account for the results, indicates that the enlarging thymic lobe contains both large and small blast cells, a heterogenous group of medium lymphocytes, erythroid cells, and two types of very small lymphocytes. The distinction between early erythroid cells and some lymphocytes, despite this detailed analysis is very difficult, but it is possible in enlarging thymic lobes that up to 42% of the lymphoid cells may have erythroid characteristics. PMID:466698

  3. Epigenetic Determinants of Erythropoiesis: Role of the Histone Methyltransferase SetD8 in Promoting Erythroid Cell Maturation and Survival.

    PubMed

    DeVilbiss, Andrew W; Sanalkumar, Rajendran; Hall, Bryan D R; Katsumura, Koichi R; de Andrade, Isabela Fraga; Bresnick, Emery H

    2015-06-01

    Erythropoiesis, in which committed progenitor cells generate millions of erythrocytes daily, involves dramatic changes in the chromatin structure and transcriptome of erythroblasts, prior to their enucleation. While the involvement of the master-regulatory transcription factors GATA binding protein 1 (GATA-1) and GATA-2 in this process is established, the mechanistic contributions of many chromatin-modifying/remodeling enzymes in red cell biology remain enigmatic. We demonstrated that SetD8, a histone methyltransferase that catalyzes monomethylation of histone H4 at lysine 20 (H4K20me1), is a context-dependent GATA-1 corepressor in erythroid cells. To determine whether SetD8 controls erythroid maturation and/or function, we used a small hairpin RNA (shRNA)-based loss-of-function strategy in a primary murine erythroblast culture system. In this system, SetD8 promoted erythroblast maturation and survival, and this did not involve upregulation of the established regulator of erythroblast survival Bcl-x(L). SetD8 catalyzed H4K20me1 at a critical Gata2 cis element and restricted occupancy by an enhancer of Gata2 transcription, Scl/TAL1, thereby repressing Gata2 transcription. Elevating GATA-2 levels in erythroid precursors yielded a maturation block comparable to that induced by SetD8 downregulation. As lowering GATA-2 expression in the context of SetD8 knockdown did not rescue erythroid maturation, we propose that SetD8 regulation of erythroid maturation involves multiple target genes. These results establish SetD8 as a determinant of erythroid cell maturation and provide a framework for understanding how a broadly expressed histone-modifying enzyme mediates cell-type-specific GATA factor function. PMID:25855754

  4. Zfp36l2 is required for self-renewal of early erythroid BFU-E progenitors

    PubMed Central

    Zhang, Lingbo; Prak, Lina; Rayon-Estrada, Violeta; Thiru, Prathapan; Flygare, Johan; Lim, Bing; Lodish, Harvey F.

    2013-01-01

    Stem cells and progenitors in many lineages undergo self- renewing divisions, but the extracellular and intracellular proteins that regulate this process are largely unknown. Glucocorticoids stimulate red cell formation by promoting self-renewal of early erythroid burst forming unit-erythrocyte (BFU-E) progenitors1-4. Here we show that the RNA binding protein Zfp36l2 is a transcriptional target of the glucocorticoid receptor (GR) in BFU-Es and is required for BFU-E self-renewal. Zfp36l2 is normally downregulated during erythroid differentiation from the BFU-E stage but its expression is maintained by all tested GR agonists that stimulate BFU-E self-renewal, and the GR binds to several potential enhancer regions of Zfp36l2. Knockdown of Zfp36l2 in cultured BFU-E cells did not affect the rate of cell division but disrupted glucocorticoid-induced BFU-E self-renewal, and knockdown of Zfp36l2 in transplanted erythroid progenitors prevented expansion of erythroid lineage progenitors normally seen following induction of anemia by phenylhydrazine treatment. Zfp36l2 preferentially binds to mRNAs that are induced or maintained at high expression levels during terminal erythroid differentiation and negatively regulates their expression levels. Thus Zfp36l2 functions as part of molecular switch promoting BFU-E self-renewal and thus a subsequent increase in the total numbers of CFU-E progenitors and erythroid cells that are generated. PMID:23748442

  5. Olive leaf components apigenin 7-glucoside and luteolin 7-glucoside direct human hematopoietic stem cell differentiation towards erythroid lineage.

    PubMed

    Samet, Imen; Villareal, Myra O; Motojima, Hideko; Han, Junkyu; Sayadi, Sami; Isoda, Hiroko

    2015-06-01

    The generation of blood cellular components from hematopoietic stem cells is important for the therapy of a broad spectrum of hematological disorders. In recent years, several lines of evidence suggested that certain nutrients, vitamins and flavonoids may have important roles in controlling the stem cell fate decision by maintaining their self-renewal or stimulating the lineage-specific differentiation. In this study, main olive leaf phytochemicals oleuropein (Olp), apigenin 7-glucoside (Api7G) and luteolin 7-glucoside (Lut7G) were investigated for their potential effects on hematopoietic stem cell differentiation using both phenotypic and molecular analysis. Oleuropein and the combination of the three compounds enhanced the differentiation of CD34+ cells into myelomonocytic cells and lymphocytes progenitors and inhibited the commitment to megakaryocytic and erythroid lineages. Treatment with Lut7G stimulated both the erythroid and the myeloid differentiation, while treatment with Api7G specifically induced the differentiation of CD34+ cells towards the erythroid lineage and inhibited the myeloid differentiation. Erythroid differentiation induced by Api7G and Lut7G treatments was confirmed by the increase in hemoglobin genes expressions (α-hemoglobin, β-hemoglobin and γ-hemoglobin) and erythroid transcription factor GATA1 expression. As revealed by microarray analysis, the mechanisms underlying the erythroid differentiation-inducing effect of Api7G on hematopoietic stem cells involves the activation of JAK/STAT signaling pathway. These findings prove the differentiation-inducing effects of olive leaf compounds on hematopoietic stem cells and highlight their potential use in the ex vivo generation of blood cells. PMID:26299581

  6. Simvastatin and t-butylhydroquinone suppress KLF1 and BCL11A gene expression and additively increase fetal hemoglobin in primary human erythroid cells

    PubMed Central

    Macari, Elizabeth R.; Schaeffer, Emily K.; West, Rachel J.

    2013-01-01

    Although increased fetal hemoglobin (HbF) levels have proven benefit for people with β-hemoglobinopathies, all current HbF-inducing agents have limitations. We previously reported that drugs that activate the NRF2 antioxidant response signaling pathway increase HbF in primary human erythroid cells. In an attempt to increase HbF levels achieved with NRF2 activators, in the present study, we investigated potential complementary activity between these agents and HMG-CoA reductase inhibitors (statins) based on their ability to induce KLF2 protein levels. Experiments in K562 cells showed that simvastatin increased KLF2 mRNA and protein and KLF2 binding to HS2 of the β-globin locus control region and enhanced γ-globin mRNA production by the NRF2 activator Tert-butylhydroquinone (tBHQ). When tested in differentiating primary human erythroid cells, simvastatin induced HbF alone and additively with tBHQ, but it did not increase KLF2 mRNA or locus control region binding above levels seen with normal differentiation. Investigating alternative mechanisms of action, we found that both simvastatin and tBHQ suppress β-globin mRNA and KLF1 and BCL11A mRNA and protein, similar to what is seen in people with an HPFH phenotype because of KLF1 haploinsufficiency. These findings identify statins as a potential class of HbF-inducing agents and suggest a novel mechanism of action based on pharmacologic suppression of KLF1 and BCL11A gene expression. PMID:23223429

  7. Enhancements of the production of bilirubin and the expression of β-globin by carbon monoxide during erythroid differentiation.

    PubMed

    Mu, Anfeng; Li, Ming; Tanaka, Masakazu; Adachi, Yasushi; Tai, Tran Tien; Liem, Pham Hieu; Izawa, Shingo; Furuyama, Kazumichi; Taketani, Shigeru

    2016-05-01

    Heme is degraded by heme oxygenase to form iron, carbon monoxide (CO), and biliverdin. However, information about the catabolism of heme in erythroid cells is limited. In this study, we showed the production and export of bilirubin in murine erythroleukemia (MEL) cells. The production of bilirubin by MEL cells was enhanced when heme synthesis was induced. When mouse bone marrow cells were induced with erythropoietin to differentiate into erythroid cells, the synthesis of bilirubin increased. The expression of β-globin was enhanced by CO at the transcriptional level. These results indicate that constant production of CO from heme regulates erythropoiesis. PMID:27087140

  8. Murine tribbles homolog 2 deficiency affects erythroid progenitor development and confers macrocytic anemia on mice.

    PubMed

    Lin, Kou-Ray; Yang-Yen, Hsin-Fang; Lien, Huang-Wei; Liao, Wei-Hao; Huang, Chang-Jen; Lin, Liang-In; Li, Chung-Leung; Yen, Jeffrey Jong-Young

    2016-01-01

    Tribbles homolog 2 (Trib2) is a member of Tribbles protein pseudokinases and involves in apoptosis, autoimmunity, cancer, leukemia and erythropoiesis, however, the physiological function of Trib2 in hematopoietic system remains to be elucidated. Here, we report that Trib2 knockout (KO) mice manifest macrocytic anemia and increase of T lymphocytes. Although Trib2 deficient RBCs have similar half-life as the control RBCs, Trib2 KO mice are highly vulnerable to oxidant-induced hemolysis. Endogenous Trib2 mRNA is expressed in early hematopoietic progenitors, erythroid precursors, and lymphoid lineages, but not in mature RBCs, myeloid progenitors and granulocytes. Consistently, flow cytometric analysis and in vitro colony forming assay revealed that deletion of Trib2 mainly affected erythroid lineage development, and had no effect on either granulocyte or megakaryocyte lineages in bone marrow. Furthermore, a genetic approach using double knockout of Trib2 and C/ebpα genes in mice suggested that Trib2 promotes erythropoiesis independent of C/ebpα proteins in vivo. Finally, ectopic expression of human Trib2 in zebrafish embryos resulted in increased expression of erythropoiesis-related genes and of hemoglobin. Taking all data together, our results suggest that Trib2 positively promotes early erythrocyte differentiation and is essential for tolerance to hemolysis. PMID:27550848

  9. Immunocytochemical mapping of the hemoglobin biosynthesis site in amphibian erythroid cells.

    PubMed

    Cianciarullo, A M; Beçak, W; Soares, M J

    1999-06-01

    During the past 25 years, several studies have attempted to determine the site of integration of the heme and the four globin chains in vertebrate erythroid cells that is important in the formation of the hemoglobin molecule. Mitochondrion-like organelles or hemosomes were pointed out as responsible for this task. We performed several experiments to investigate this hypothesis. The intracellular distribution of hemoglobin in amphibian erythroid cells was detected by post-embedding immuno-electron microscopy, using a polyclonal anti-human hemoglobin-proteinA-gold complex. Hemoglobin mapping showed an intense labeling in the cell cytoplasm, but none in cytoplasmic structures such as endoplasmic reticulum, mitochondria, mitochondrion-like organelles, Golgi complex, ribosomes or ferruginous inclusions. The mitochondrial fraction obtained according to the protocol described for some authors, showed by ultrastructural examination that this fraction has a heterogeneous content, also composed by microvesicles rich in cytoplasmic hemoglobin, an artifact generated by mechanical action during cell fractionation. Thus, when this fraction is lysed and its content submitted to electrophoresis, hemoglobin bands would be found inevitably, causing false-positive results, erroneously attributed to hemoglobin content of mitochondrion-like organelles. Our data do not confirm the hypothesis that the final hemoglobin biosynthesis occurs inside mitochondrion-like organelles. They suggest that the hemoglobin molecule be assembled in the erythrocyte cytoplasm outside of mitochondria or hemosomes. PMID:10481306

  10. Erythroid 5-aminolevulinate synthase mediates the upregulation of membrane band 3 protein expression by iron.

    PubMed

    Huang, Qianchuan; Li, Jinying; Feng, Weihua; Xu, Yanqun; Huang, Zhenxia; Lv, Shuqing; Zhou, Hong; Gao, Lei

    2010-03-01

    Iron deficiency leads to abnormal expression and function of band 3 protein in erythrocytes, but the underlying mechanisms remain elusive. The mRNA of erythroid-specific 5-aminolevulinate synthase (eALAS) contains an iron response element and the eALAS protein is an important mediator of iron utilization by erythrocytes. In this study, we investigated the effect of short hairpin RNA (shRNA) mediated silencing of eALAS on the expression of band 3 protein induced by iron. By real-time RT-PCR and Western blot we showed that at mRNA and protein level iron-induced expression of band 3 protein was lower in eALAS-shRNA transfected K562 cells than in control cells. Of note, the lowest expression was detected in K562 cells cultured in iron deficiency condition (p < 0.01). Thus either iron deficiency or depletion of eALAS could suppress the expression of erythroid band 3 protein. These results demonstrated for the first time that iron and the iron-regulatory system regulate the expression of the erythrocyte membrane proteins. PMID:20087844

  11. Protein 4.1R–deficient mice are viable but have erythroid membrane skeleton abnormalities

    PubMed Central

    Shi, Zheng-Tao; Afzal, Veena; Coller, Barry; Patel, Dipti; Chasis, Joel A.; Parra, Marilyn; Lee, Gloria; Paszty, Chris; Stevens, Mary; Walensky, Loren; Peters, Luanne L.; Mohandas, Narla; Rubin, Edward; Conboy, John G.

    1999-01-01

    A diverse family of protein 4.1R isoforms is encoded by a complex gene on human chromosome 1. Although the prototypical 80-kDa 4.1R in mature erythrocytes is a key component of the erythroid membrane skeleton that regulates erythrocyte morphology and mechanical stability, little is known about 4.1R function in nucleated cells. Using gene knockout technology, we have generated mice with complete deficiency of all 4.1R protein isoforms. These 4.1R-null mice were viable, with moderate hemolytic anemia but no gross abnormalities. Erythrocytes from these mice exhibited abnormal morphology, lowered membrane stability, and reduced expression of other skeletal proteins including spectrin and ankyrin, suggesting that loss of 4.1R compromises membrane skeleton assembly in erythroid progenitors. Platelet morphology and function were essentially normal, indicating that 4.1R deficiency may have less impact on other hematopoietic lineages. Nonerythroid 4.1R expression patterns, viewed using histochemical staining for lacZ reporter activity incorporated into the targeted gene, revealed focal expression in specific neurons in the brain and in select cells of other major organs, challenging the view that 4.1R expression is widespread among nonerythroid cells. The 4.1R knockout mice represent a valuable animal model for exploring 4.1R function in nonerythroid cells and for determining pathophysiological sequelae to 4.1R deficiency. PMID:9927493

  12. In Vitro Differentiation of Embryonic Stem Cells into Hematopoietic Lineage: Towards Erythroid Progenitor's Production.

    PubMed

    Fauzi, Iliana; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2016-01-01

    Embryonic stem cells (ESCs) differentiation via embryoid body (EB) formation is an established method that generates the three germ layers. However, EB differentiation poses several problems including formation of heterogeneous cell populations. Herein, we described a differentiation protocol on enhancing mesoderm derivation from murine ESCs (mESCs) using conditioned medium (CM) from HepG2 cells. We used this technique to direct hematopoiesis by generating "embryoid-like" colonies (ELCs) from murine (m) ESCs without following standard formation of EBs. Our CM-mESCs group yielded an almost fivefold increase in ELC formation (p ≤ 0.05) and higher expression of mesoderm genes;-Brachyury-T, Goosecoid, and Flk-1 compared with control mESCs group. Hematopoietic colony formation from CM-mESCs was also enhanced by twofold at days 7 and 14 with earlier colony commitment compared to control mESCs (p ≤ 0.05). This early clonogenic capacity was confirmed morphologically by the presence of nucleated erythrocytes and macrophages as early as day 7 in culture using standard 14-day colony-forming assay. Early expression of hematopoietic primitive (ζ-globin) and definitive (β-globin) erythroid genes and proteins was also observed by day 7 in the CM-treated culture. These data indicate that hematopoietic cells more quickly differentiate from CM-treated, compared with those using standard EB approaches, and provide an efficient bioprocess platform for erythroid-specific differentiation of ESCs. PMID:26160454

  13. Transcription of the hypersensitive site HS2 enhancer in erythroid cells

    SciTech Connect

    Tuan, D.; Suming Kong; Hu, K. )

    1992-12-01

    In the human genome, the erythroid-specific hypersensitive site HS2 enhancer regulates the transcription of the downstream [beta]-like globin genes 10-50 kilobases away. The mechanism of HS2 enhancer function is not known. The present study employs RNA protection assays to analyze the transcriptional status of the HS2 enhancer in transfected recombinant chloramphenicol acetyltransferase (CAT) plasmids. In erythroid K562 cells in which the HS2 enhancer is active, the HS2 sequence directs the synthesis of long enhancer transcripts that are initiated apparently from within the enhancer and elongated through the intervening DNA into the cis-linked CAT gene. In nonerythroid HL-60 cells in which the HS2 enhancer is inactive, long enhancer transcripts are not detectable. Splitting the HS2 enhancer between two tandem Ap1 sites abolishes the synthesis of a group of long enhancer transcripts and results in loss of enhancer function and transcriptional silencing of the cis-linked CAT gene. In directing the synthesis of RNA through the intervening DNA and the gene by a tracking and transcription mechanism, the HS2 enhancer may (i) open up the chromatin structure of a gene domain and (ii) deliver enhancer binding proteins to the promoter sequence where they may stimulate the transcription of the gene at the cap site. 42 refs., 4 figs., 1 tab.

  14. Structural and functional characterization of an atypical activation domain in erythroid Kruppel-like factor (EKLF).

    PubMed

    Mas, Caroline; Lussier-Price, Mathieu; Soni, Shefali; Morse, Thomas; Arseneault, Geneviève; Di Lello, Paola; Lafrance-Vanasse, Julien; Bieker, James J; Omichinski, James G

    2011-06-28

    Erythroid Krüppel-like factor (EKLF) plays an important role in erythroid development by stimulating β-globin gene expression. We have examined the details by which the minimal transactivation domain (TAD) of EKLF (EKLFTAD) interacts with several transcriptional regulatory factors. We report that EKLFTAD displays homology to the p53TAD and, like the p53TAD, can be divided into two functional subdomains (EKLFTAD1 and EKLFTAD2). Based on sequence analysis, we found that EKLFTAD2 is conserved in KLF2, KLF4, KLF5, and KLF15. In addition, we demonstrate that EKLFTAD2 binds the amino-terminal PH domain of the Tfb1/p62 subunit of TFIIH (Tfb1PH/p62PH) and four domains of CREB-binding protein/p300. The solution structure of the EKLFTAD2/Tfb1PH complex indicates that EKLFTAD2 binds Tfb1PH in an extended conformation, which is in contrast to the α-helical conformation seen for p53TAD2 in complex with Tfb1PH. These studies provide detailed mechanistic information into EKLFTAD functions as well as insights into potential interactions of the TADs of other KLF proteins. In addition, they suggest that not only have acidic TADs evolved so that they bind using different conformations on a common target, but that transitioning from a disordered to a more ordered state is not a requirement for their ability to bind multiple partners. PMID:21670263

  15. Development of methods for characterizing fetal and adult somatic mutations detected in human erythroid precursor

    SciTech Connect

    Langlois, R.G.; Manchester, D.K.

    1994-12-31

    The glycophorin A (GPA) assay was developed to quantify somatic mutations in humans by measuring the frequency of peripheral erythrocytes with mutant phenotypes that are presumed to be progeny of mutated erythroid precursor cells. This assay has been used to identify GPA variant cells in unexposed individuals at a frequency of {approximately}10 per million erythrocytes, and to demonstrate significant increases in variant frequency after mutagenic exposures. Characterization of the mutations responsible for these variant cells requires that the assay be modified to allow flow analysis and sorting of variant erythroid precursor cells that contain nucleic acids. Cord blood samples contain low levels of both reticulocytes and nucleated erythrocytes. We have developed enrichment methods using centrifugation that yield samples containing up to 30% nucleated erythrocytes, and immunomagnetic separation methods that yield samples containing up to 90% reticulocytes. Enrichment methods for these two cell types are also being developed for adult bone marrow samples. We have confirmed that enrichment and labeling with a nucleic acid-specific dye are compatible with GPA analysis of erythrocytes, reticulocytes, and nucleated erythrocytes. Enriched samples have been successfully used for flow cytometric detection of GPA variant reticulocytes in cord blood. PCR-based analysis methods are being developed for molecular characterization of sorted variant cells at the mRNA level.

  16. Pharmacological Induction of Human Fetal Globin Gene in Hydroxyurea-Resistant Primary Adult Erythroid Cells.

    PubMed

    Chou, Yu-Chi; Chen, Ruei-Lin; Lai, Zheng-Sheng; Song, Jen-Shin; Chao, Yu-Sheng; Shen, Che-Kun James

    2015-07-01

    Pharmacological induction of the fetal γ globin gene and the consequent formation of HbF (α2/γ2) in adult erythroid cells are one feasible therapeutic strategy for sickle cell disease (SCD) and severe β-thalassemias. Hydroxyurea (HU) is the current drug of choice for SCD, but serious side effects limit its clinical use. Moreover, 30 to 50% of patients are irresponsive to HU treatment. We have used high-throughput screening to identify benzo[de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one and its derivatives (compounds I to VI) as potent γ globin inducers. Of the compounds, I to V exert superior γ globin induction and have better therapeutic potential than HU, likely because of their activation of the p38 mitogen-activated protein kinase (MAPK) signaling pathway and modulation of expression levels and/or chromosome binding of γ globin gene regulators, including BCL11A, and chromatin structure over the γ globin promoter. Unlike sodium butyrate (NaB), the global levels of acetylated histones H3 and H4 are not changed by compound II treatment. Remarkably, compound II induces the γ globin gene in HU-resistant primary human adult erythroid cells, the p38 signaling pathway of which appears to be irresponsive to HU and NaB as well as compound II. This study provides a new framework for the development of new and superior compounds for treating SCD and severe β-thalassemias. PMID:25986606

  17. Transcription of the hypersensitive site HS2 enhancer in erythroid cells.

    PubMed Central

    Tuan, D; Kong, S; Hu, K

    1992-01-01

    In the human genome, the erythroid-specific hypersensitive site HS2 enhancer regulates the transcription of the downstream beta-like globin genes 10-50 kilobases away. The mechanism of HS2 enhancer function is not known. The present study employs RNA protection assays to analyze the transcriptional status of the HS2 enhancer in transfected recombinant chloramphenicol acetyltransferase (CAT) plasmids. In erythroid K562 cells in which the HS2 enhancer is active, the HS2 sequence directs the synthesis of long enhancer transcripts that are initiated apparently from within the enhancer and elongated through the intervening DNA into the cis-linked CAT gene. In nonerythroid HL-60 cells in which the HS2 enhancer is inactive, long enhancer transcripts are not detectable. Splitting the HS2 enhancer between two tandem Ap1 sites abolishes the synthesis of a group of long enhancer transcripts and results in loss of enhancer function and transcriptional silencing of the cis-linked CAT gene. In directing the synthesis of RNA through the intervening DNA and the gene by a tracking and transcription mechanism, the HS2 enhancer may (i) open up the chromatin structure of a gene domain and (ii) deliver enhancer binding proteins to the promoter sequence where they may stimulate the transcription of the gene at the cap site. Images PMID:1454801

  18. Murine tribbles homolog 2 deficiency affects erythroid progenitor development and confers macrocytic anemia on mice

    PubMed Central

    Lin, Kou-Ray; Yang-Yen, Hsin-Fang; Lien, Huang-Wei; Liao, Wei-Hao; Huang, Chang-Jen; Lin, Liang-In; Li, Chung-Leung; Yen, Jeffrey Jong-Young

    2016-01-01

    Tribbles homolog 2 (Trib2) is a member of Tribbles protein pseudokinases and involves in apoptosis, autoimmunity, cancer, leukemia and erythropoiesis, however, the physiological function of Trib2 in hematopoietic system remains to be elucidated. Here, we report that Trib2 knockout (KO) mice manifest macrocytic anemia and increase of T lymphocytes. Although Trib2 deficient RBCs have similar half-life as the control RBCs, Trib2 KO mice are highly vulnerable to oxidant-induced hemolysis. Endogenous Trib2 mRNA is expressed in early hematopoietic progenitors, erythroid precursors, and lymphoid lineages, but not in mature RBCs, myeloid progenitors and granulocytes. Consistently, flow cytometric analysis and in vitro colony forming assay revealed that deletion of Trib2 mainly affected erythroid lineage development, and had no effect on either granulocyte or megakaryocyte lineages in bone marrow. Furthermore, a genetic approach using double knockout of Trib2 and C/ebpα genes in mice suggested that Trib2 promotes erythropoiesis independent of C/ebpα proteins in vivo. Finally, ectopic expression of human Trib2 in zebrafish embryos resulted in increased expression of erythropoiesis-related genes and of hemoglobin. Taking all data together, our results suggest that Trib2 positively promotes early erythrocyte differentiation and is essential for tolerance to hemolysis. PMID:27550848

  19. Strategies for achieving sustained competitive advantage.

    PubMed

    Schlosser, J R

    1987-06-01

    Sound strategic planning, even in the midst of unprecedented uncertainty and turmoil, is a critical element of every successful health care organization's action plan. The author examines how one organization has responded to the changing demands of the marketplace and a dramatically changed reimbursement system through appropriate strategic planning, selective downsizing on certain fronts and new product development expansion on others. The result is an organization molded to the new environment. It is no longer based on an illness-model hospital but rather focuses on a vertically integrated multi-health cluster intent on capturing market share by providing a single source continuum of health care. PMID:10301856

  20. Achieving and sustaining quality in healthcare.

    PubMed

    Sr Mary Jean Ryan

    2004-01-01

    SSM Health Care (SSMHC), the first healthcare recipient of the Malcolm Baldrige National Quality Award, has been cited by both Baldrige and the Joint Commission on Accreditation of Healthcare Organizations as having a culture of continuous quality improvement (CQI). SSM Health Care began to implement CQI systemwide in 1990. CQI provided the foundation for other strategies that served to further weave quality improvement into the fabric of the organization's culture. It gave SSMHC's people the tools and techniques to make improvements, created an environment of teamwork, and introduced the concept of improving processes. Using the Baldrige Criteria for Performance Excellence as a business model helped SSMHC to see how various organizational functions should link and to discover gaps in the linkage within its own organization. Baldrige feedback reports identified opportunities that could then be prioritized and the resulting improvements implemented. Overall, the Baldrige model gave a focused approach to what had been scattered improvement efforts. SSM Health Care considers the Baldrige model the best way for an organization to get better faster. PMID:15055826

  1. Achieving Sustainability in Learning and Teaching Initiatives

    ERIC Educational Resources Information Center

    Brew, Angela; Cahir, Jayde

    2014-01-01

    Universities have a long history of change in learning and teaching to suit various government initiatives and institutional priorities. Academic developers now are frequently required to address strategic learning and teaching priorities. This paper asks how, in such a context, academic developers can ensure that work they do in relation to one…

  2. Achieving Sustainable Construction in Affordable Housing

    SciTech Connect

    Barcik, M.K.; Creech, D.B.; Ternes, M.P.

    1998-12-07

    An energy-efficient design and construction checklist and information sheets on energy-efficient design and construction are two products being developed. These products will help affordable housing providers take the first steps toward a whole-house approach to the design and implementation of energy-efficient construction practices. The checklist presents simple and clear guidance on energy improvements that can be readily addressed now by most affordable housing providers. The information sheets complement the checklist by providing installation instructions and material specifications that are accompanied by detailed graphics. The information sheets also identify benefits of recommended energy-efficiency measures and procedures including cost savings and impacts on health and comfort. This paper presents details on the checklist and information sheets and discusses their use in two affordable housing projects.

  3. How Schools Sustain Success

    ERIC Educational Resources Information Center

    Chrisman, Valerie

    2005-01-01

    A growing number of the US schools, under the microscope of increased accountability, are identified as underperforming on the basis of low-test scores. Yet sustained increases in student achievement are problematic for underperforming schools.

  4. Erythroid cell growth and differentiation in vitro in the simulated microgravity environment of the NASA rotating wall vessel bioreactor

    NASA Technical Reports Server (NTRS)

    Sytkowski, A. J.; Davis, K. L.

    2001-01-01

    Prolonged exposure of humans and experimental animals to the altered gravitational conditions of space flight has adverse effects on the lymphoid and erythroid hematopoietic systems. Although some information is available regarding the cellular and molecular changes in lymphocytes exposed to microgravity, little is known about the erythroid cellular changes that may underlie the reduction in erythropoiesis and resultant anemia. We now report a reduction in erythroid growth and a profound inhibition of erythropoietin (Epo)-induced differentiation in a ground-based simulated microgravity model system. Rauscher murine erythroleukemia cells were grown either in tissue culture vessels at 1 x g or in the simulated microgravity environment of the NASA-designed rotating wall vessel (RWV) bioreactor. Logarithmic growth was observed under both conditions; however, the doubling time in simulated microgravity was only one-half of that seen at 1 x g. No difference in apoptosis was detected. Induction with Epo at the initiation of the culture resulted in differentiation of approximately 25% of the cells at 1 x g, consistent with our previous observations. In contrast, induction with Epo at the initiation of simulated microgravity resulted in only one-half of this degree of differentiation. Significantly, the growth of cells in simulated microgravity for 24 h prior to Epo induction inhibited the differentiation almost completely. The results suggest that the NASA RWV bioreactor may serve as a suitable ground-based microgravity simulator to model the cellular and molecular changes in erythroid cells observed in true microgravity.

  5. MicroRNA-486-5p is an erythroid oncomiR of the myeloid leukemias of Down syndrome

    PubMed Central

    Shaham, Lital; Vendramini, Elena; Ge, Yubin; Goren, Yaron; Birger, Yehudit; Tijssen, Marloes R.; McNulty, Maureen; Geron, Ifat; Schwartzman, Omer; Goldberg, Liat; Chou, Stella T.; Pitman, Holly; Weiss, Mitchell J.; Michaeli, Shulamit; Sredni, Benjamin; Göttgens, Berthold; Crispino, John D.; Taub, Jeffrey W.

    2015-01-01

    Children with Down syndrome (DS) are at increased risk for acute myeloid leukemias (ML-DS) characterized by mixed megakaryocytic and erythroid phenotype and by acquired mutations in the GATA1 gene resulting in a short GATA1s isoform. The chromosome 21 microRNA (miR)-125b cluster has been previously shown to cooperate with GATA1s in transformation of fetal hematopoietic progenitors. In this study, we report that the expression of miR-486-5p is increased in ML-DS compared with non-DS acute megakaryocytic leukemias (AMKLs). miR-486-5p is regulated by GATA1 and GATA1s that bind to the promoter of its host gene ANK1. miR-486-5p is highly expressed in mouse erythroid precursors and knockdown (KD) in ML-DS cells reduced their erythroid phenotype. Ectopic expression and KD of miR-486-5p in primary fetal liver hematopoietic progenitors demonstrated that miR-486-5p cooperates with Gata1s to enhance their self renewal. Consistent with its activation of AKT, overexpression and KD experiments showed its importance for growth and survival of human leukemic cells. Thus, miR-486-5p cooperates with GATA1s in supporting the growth and survival, and the aberrant erythroid phenotype of the megakaryocytic leukemias of DS. PMID:25533034

  6. MicroRNA-486-5p is an erythroid oncomiR of the myeloid leukemias of Down syndrome.

    PubMed

    Shaham, Lital; Vendramini, Elena; Ge, Yubin; Goren, Yaron; Birger, Yehudit; Tijssen, Marloes R; McNulty, Maureen; Geron, Ifat; Schwartzman, Omer; Goldberg, Liat; Chou, Stella T; Pitman, Holly; Weiss, Mitchell J; Michaeli, Shulamit; Sredni, Benjamin; Göttgens, Berthold; Crispino, John D; Taub, Jeffrey W; Izraeli, Shai

    2015-02-19

    Children with Down syndrome (DS) are at increased risk for acute myeloid leukemias (ML-DS) characterized by mixed megakaryocytic and erythroid phenotype and by acquired mutations in the GATA1 gene resulting in a short GATA1s isoform. The chromosome 21 microRNA (miR)-125b cluster has been previously shown to cooperate with GATA1s in transformation of fetal hematopoietic progenitors. In this study, we report that the expression of miR-486-5p is increased in ML-DS compared with non-DS acute megakaryocytic leukemias (AMKLs). miR-486-5p is regulated by GATA1 and GATA1s that bind to the promoter of its host gene ANK1. miR-486-5p is highly expressed in mouse erythroid precursors and knockdown (KD) in ML-DS cells reduced their erythroid phenotype. Ectopic expression and KD of miR-486-5p in primary fetal liver hematopoietic progenitors demonstrated that miR-486-5p cooperates with Gata1s to enhance their self renewal. Consistent with its activation of AKT, overexpression and KD experiments showed its importance for growth and survival of human leukemic cells. Thus, miR-486-5p cooperates with GATA1s in supporting the growth and survival, and the aberrant erythroid phenotype of the megakaryocytic leukemias of DS. PMID:25533034

  7. CTCF and CohesinSA-1 Mark Active Promoters and Boundaries of Repressive Chromatin Domains in Primary Human Erythroid Cells

    PubMed Central

    Steiner, Laurie A.; Schulz, Vincent; Makismova, Yelena; Lezon-Geyda, Kimberly; Gallagher, Patrick G.

    2016-01-01

    Background CTCF and cohesinSA-1 are regulatory proteins involved in a number of critical cellular processes including transcription, maintenance of chromatin domain architecture, and insulator function. To assess changes in the CTCF and cohesinSA-1 interactomes during erythropoiesis, chromatin immunoprecipitation coupled with high throughput sequencing and mRNA transcriptome analyses via RNA-seq were performed in primary human hematopoietic stem and progenitor cells (HSPC) and primary human erythroid cells from single donors. Results Sites of CTCF and cohesinSA-1 co-occupancy were enriched in gene promoters in HSPC and erythroid cells compared to single CTCF or cohesin sites. Cell type-specific CTCF sites in erythroid cells were linked to highly expressed genes, with the opposite pattern observed in HSPCs. Chromatin domains were identified by ChIP-seq with antibodies against trimethylated lysine 27 histone H3, a modification associated with repressive chromatin. Repressive chromatin domains increased in both number and size during hematopoiesis, with many more repressive domains in erythroid cells than HSPCs. CTCF and cohesinSA-1 marked the boundaries of these repressive chromatin domains in a cell-type specific manner. Conclusion These genome wide data, changes in sites of protein occupancy, chromatin architecture, and related gene expression, support the hypothesis that CTCF and cohesinSA-1 have multiple roles in the regulation of gene expression during erythropoiesis including transcriptional regulation at gene promoters and maintenance of chromatin architecture. These data from primary human erythroid cells provide a resource for studies of normal and perturbed erythropoiesis. PMID:27219007

  8. miR-214 protects erythroid cells against oxidative stress by targeting ATF4 and EZH2.

    PubMed

    Gao, Ming; Liu, Yun; Chen, Yue; Yin, Chunyang; Chen, Jane-Jane; Liu, Sijin

    2016-03-01

    Nuclear factor (erythroid-derived 2) like 2 (Nrf2) is a key regulator in protecting cells against stress by targeting many anti-stress response genes. Recent evidence also reveals that Nrf2 functions partially by targeting mircroRNAs (miRNAs). However, the understanding of Nrf2-mediated cytoprotection through miRNA-dependent mechanisms is largely unknown. In the current study, we identified a direct Nrf2 targeting miRNA, miR-214, and demonstrated a protective role of miR-214 in erythroid cells against oxidative stresses generated by radiation, excess iron and arsenic (As) exposure. miR-214 expression was transcriptionally repressed by Nrf2 through a canonical antioxidant response element (ARE) within its promoter region, and this repression is ROS-dependence. The suppression of miR-214 by Nrf2 could antagonize oxidative stress-induced cell death in erythroid cells by two ways. First, miR-214 directly targeted ATF4, a crucial transcriptional factor involved in anti-stress responses, down regulation of miR-214 releases the repression of ATF4 translation and leads to increased ATF4 protein content. Second, miR-214 was able to prevent cell death by targeting EZH2, the catalytic core component of PRC2 complex that is responsible for tri-methylation reaction at lysine 27 (K27) of histone 3 (H3) (H3K27me3), by which As-induced miR-214 reduction resulted in an increased global H3K27me3 level and a compromised overexpression of a pro-apoptotic gene Bim. These two pathways downstream of miR-214 synergistically cooperated to antagonize erythroid cell death upon oxidative stress. Our combined data revealed a protective role of miR-214 signaling in erythroid cells against oxidative stress, and also shed new light on Nrf2-mediated cytoprotective machinery. PMID:26791102

  9. Nuclear erythroid 2-related factor 2: a novel potential therapeutic target for liver fibrosis.

    PubMed

    Yang, Jing-Jing; Tao, Hui; Huang, Cheng; Li, Jun

    2013-09-01

    Hepatic stellate cells (HSC) are the key fibrogenic cells of the liver. HSC activation is a process of cellular transdifferentiation that occurs upon liver injury, but the mechanisms underlying liver fibrosis are unknown. Nuclear erythroid 2-related factor 2 (Nrf2) is an oxidative stress-mediated transcription factor with a variety of downstream targets aimed at cytoprotection. However, Nrf2 has recently been implicated as a new therapeutic target for the treatment of liver fibrosis. This review focuses on the transcriptional repressors that either control liver injury or regulate specific fibrogenic functions of liver fibrosis. We also show that Nrf2 may reveal significant gene expression changes, suggesting that Nrf2 activation may ameliorate liver fibrosis. PMID:23793039

  10. Restoration of hemoglobin A synthesis in erythroid cells from peripheral blood of thalassemic patients

    PubMed Central

    Lacerra, Giuseppina; Sierakowska, Halina; Carestia, Clementina; Fucharoen, Suthat; Summerton, James; Weller, Dwight; Kole, Ryszard

    2000-01-01

    Mononuclear cells from peripheral blood of thalassemic patients were treated with morpholino oligonucleotides antisense to aberrant splice sites in mutant β-globin precursor mRNAs (pre-mRNAs). The oligonucleotides restored correct splicing and translation of β-globin mRNA, increasing the hemoglobin (Hb) A synthesis in erythroid cells from patients with IVS2–654/βE, IVS2–745/IVS2–745, and IVS2–745/IVS2–1 genotypes. The maximal Hb A level for repaired IVS2–745 mutation was ≈30% of normal; Hb A was still detectable 9 days after a single treatment with oligonucleotide. Thus, expression of defective β-globin genes was repaired and significant level of Hb A was restored in a cell population that would be targeted in clinical applications of this approach. PMID:10944225

  11. Nuclear Factor-Erythroid-2-Related Factor 2 in Aging and Lung Fibrosis.

    PubMed

    Swamy, Shobha M; Rajasekaran, Namakkal S; Thannickal, Victor J

    2016-07-01

    Aging and age-related diseases have been associated with elevated oxidative stress, which may be related to increased production of reactive species and/or a deficiency in antioxidant defenses. The nuclear factor-erythroid-2-related factor 2 (Nrf2)-mediated antioxidant response pathway maintains cellular reduction-oxidation homeostasis by inducing the transcription of an array of cytoprotective genes. However, there is evidence of impaired Nrf2 response in aging contributing to age-related fibrotic diseases. Herein, we review mechanisms for the dysregulation of Nrf2 signaling in aging. This understanding will pave the way for the design of novel therapeutic strategies that restore Nrf2 signaling to reestablish cellular homeostasis in aging and age-related fibrotic diseases. PMID:27338106

  12. Lifetime achievement

    NASA Astrophysics Data System (ADS)

    Carlowicz, Michael

    The American Association for the Advancement of Science (AAAS) is accepting nominations for the 1996 Philip Hauge Abelson Prize. The prize is awarded annually to either a public servant who has made sustained contributions to the advancement of science or to scientists who have distinguished themselves for both the quality of their work and their leadership in the scientific community.

  13. Parvovirus B19 Replication and Expression in Differentiating Erythroid Progenitor Cells.

    PubMed

    Bua, Gloria; Manaresi, Elisabetta; Bonvicini, Francesca; Gallinella, Giorgio

    2016-01-01

    The pathogenic Parvovirus B19 (B19V) is characterized by a strict adaptation to erythroid progenitor cells (EPCs), a heterogeneous population of differentiating cells with diverse phenotypic and functional properties. In our work, we studied the dynamics of B19V infection in EPCs in dependence on the cell differentiation stage, in terms of distribution of infected cells, synthesis of viral nucleic acids and production of infectious virus. EPCs at early differentiation stage led to an abortive infection, without viral genome replication and a very low transcriptional activity. EPCs at later stages were permissive, with highest levels of viral replicative activity at day 9 (+3.0 Log from 2 to 48 hpi) and lower levels at day 18 (+1.5 Log from 2 to 48 hpi). B19V DNA increment was in accordance with the percentage of cells positive to flow-FISH assay (41.4% at day 9, 1.1% at day 18). Quantitation of total RNA indicated a close association of genome replication and transcription with viral RNA accumulation within infected cells related to viral DNA increase during the course of infection. Analysis of the different classes of mRNAs revealed two distinct pattern of genome expression profile with a fine regulation in the frequency utilization of RNA processing signals: an early phase, when cleavage at the proximal site leading to a higher relative production of mRNA for NS protein, and a late phase, when cleavage at the distal site was more frequent leading to higher relative abundance of mRNA for VP and 11 kDA proteins. Infectious virus was released from cells at day 6-15, but not at day 18. Our results, providing a detailed description of B19V replication and expression profile in differentiating EPCs, highlight the very tight adaptation of B19V to a specific cellular target defined both by its erythroid lineage and its differentiation stage. PMID:26845771

  14. Parvovirus B19 Replication and Expression in Differentiating Erythroid Progenitor Cells

    PubMed Central

    Bua, Gloria; Manaresi, Elisabetta; Bonvicini, Francesca; Gallinella, Giorgio

    2016-01-01

    The pathogenic Parvovirus B19 (B19V) is characterized by a strict adaptation to erythroid progenitor cells (EPCs), a heterogeneous population of differentiating cells with diverse phenotypic and functional properties. In our work, we studied the dynamics of B19V infection in EPCs in dependence on the cell differentiation stage, in terms of distribution of infected cells, synthesis of viral nucleic acids and production of infectious virus. EPCs at early differentiation stage led to an abortive infection, without viral genome replication and a very low transcriptional activity. EPCs at later stages were permissive, with highest levels of viral replicative activity at day 9 (+3.0 Log from 2 to 48 hpi) and lower levels at day 18 (+1.5 Log from 2 to 48 hpi). B19V DNA increment was in accordance with the percentage of cells positive to flow-FISH assay (41.4% at day 9, 1.1% at day 18). Quantitation of total RNA indicated a close association of genome replication and transcription with viral RNA accumulation within infected cells related to viral DNA increase during the course of infection. Analysis of the different classes of mRNAs revealed two distinct pattern of genome expression profile with a fine regulation in the frequency utilization of RNA processing signals: an early phase, when cleavage at the proximal site leading to a higher relative production of mRNA for NS protein, and a late phase, when cleavage at the distal site was more frequent leading to higher relative abundance of mRNA for VP and 11 kDA proteins. Infectious virus was released from cells at day 6–15, but not at day 18. Our results, providing a detailed description of B19V replication and expression profile in differentiating EPCs, highlight the very tight adaptation of B19V to a specific cellular target defined both by its erythroid lineage and its differentiation stage. PMID:26845771

  15. The exon-intron organization of the human erythroid [beta]-spectrin gene

    SciTech Connect

    Amin, K.M.; Forget, B.G. ); Scarpa, A.L.; Curtis, P.J. ); Winkelmann, J.C. )

    1993-10-01

    The human erythrocyte [beta]-spectrin gene DNA has been cloned from overlapping human genomic phage and cosmid recombinants. The entire erythroid [beta]-spectrin mRNA is encoded by 32 exons that range in size from 49 to 871 bases. The exon/intron junctions have been identified and the exons mapped. There is no correlation between intron positions and the repeat units of 106 amino acids within domain II of the [beta]-spectrin gene. The scatter of the introns over the 17 repeats argues against the 106-amino-acid unit representing a minigene that underwent repeated duplication resulting in the present [beta]-spectrin gene. In fact, the two largest exons, exon 14 (871 bp) and 16 (757 bp), extend over 4 and 3 repeat units of 106 amino acids, respectively, while repeat [beta]10 is encoded by 4 exons. No single position of an intron in the [beta]-spectrin gene is conserved between any of the 17 [beta]-spectrin and 22 [alpha]-spectrin repeat units. The nucleotide sequences of the exon/intron boundaries conform to the consensus splice site sequences except for exon 20, whose 5[prime] donor splice-site sequence begins with GC. The [beta]-spectrin isoform present in the human brain, the skeletal muscle, and the cardiac muscle is an alternatively spliced product of the erythroid [beta]-spectrin gene. This splice site is located within the coding sequences of exon 32 and its utilization in nonerythroid tissues leads to the use of 4 additional downstream exons with a size range of 44 to 530 bp. 55 refs., 3 figs., 3 tabs.

  16. miR-451 protects against erythroid oxidant stress by repressing 14-3-3zeta.

    PubMed

    Yu, Duonan; dos Santos, Camila O; Zhao, Guowei; Jiang, Jing; Amigo, Julio D; Khandros, Eugene; Dore, Louis C; Yao, Yu; D'Souza, Janine; Zhang, Zhe; Ghaffari, Saghi; Choi, John; Friend, Sherree; Tong, Wei; Orange, Jordan S; Paw, Barry H; Weiss, Mitchell J

    2010-08-01

    The bicistronic microRNA (miRNA) locus miR-144/451 is highly expressed during erythrocyte development, although its physiological roles are poorly understood. We show that miR-144/451 ablation in mice causes mild erythrocyte instability and increased susceptibility to damage after exposure to oxidant drugs. This phenotype is deeply conserved, as miR-451 depletion synergizes with oxidant stress to cause profound anemia in zebrafish embryos. At least some protective activities of miR-451 stem from its ability to directly suppress production of 14-3-3zeta, a phospho-serine/threonine-binding protein that inhibits nuclear accumulation of transcription factor FoxO3, a positive regulator of erythroid anti-oxidant genes. Thus, in miR-144/451(-/-) erythroblasts, 14-3-3zeta accumulates, causing partial relocalization of FoxO3 from nucleus to cytoplasm with dampening of its transcriptional program, including anti-oxidant-encoding genes Cat and Gpx1. Supporting this mechanism, overexpression of 14-3-3zeta in erythroid cells and fibroblasts inhibits nuclear localization and activity of FoxO3. Moreover, shRNA suppression of 14-3-3zeta protects miR-144/451(-/-) erythrocytes against peroxide-induced destruction, and restores catalase activity. Our findings define a novel miRNA-regulated pathway that protects erythrocytes against oxidant stress, and, more generally, illustrate how a miRNA can influence gene expression by altering the activity of a key transcription factor. PMID:20679398

  17. Decision Guidance for Sustainable Manufacturing

    ERIC Educational Resources Information Center

    Shao, Guodong

    2013-01-01

    Sustainable manufacturing has significant impacts on a company's business performance and competitiveness in today's world. A growing number of manufacturing industries are initiating efforts to address sustainability issues; however, to achieve a higher level of sustainability, manufacturers need methodologies for formally describing, analyzing,…

  18. The Effect of Baicalin as A PPAR Activator on Erythroid Differentiation of CD133+Hematopoietic Stem Cells in Umbilical Cord Blood

    PubMed Central

    Abbasi, Parvaneh; Shamsasenjan, Karim; Movassaghpour Akbari, Ali Akbar; Akbarzadehlaleh, Parvin; Dehdilani, Nima; Ejtehadifar, Mostafa

    2015-01-01

    Objective The peroxisome proliferator-activated receptors (PPARs) are a group of nu- clear receptor proteins whose functions as transcription factors regulate gene expres- sions. PPARs play essential roles in the regulation of cellular differentiation, development, and metabolism (carbohydrate, lipid, protein), and tumorigenesis of higher organisms. This study attempts to determine the effect of baicalin, a PPARγ activator, on erythroid differentiation of cluster of differentiation 133+(CD133+) cord blood hematopoietic stem cells (HSCs). Materials and Methods In this experimental study, in order to investigate the effects of the PPARγ agonists baicalin and troglitazone on erythropoiesis, we isolated CD133+ cells from human umbilical cord blood using the MACS method. Isolated cells were cultured in erythroid-inducing medium with or without various amounts of the two PPARγ activa- tors (baicalin and troglitazone). Erythroid differentiation of CD133+cord blood HSCs were assessed using microscopic morphology analysis, flow cytometric analysis of erythroid surface markers transferrin receptor (TfR) and glycophorin A (GPA) and bycolony forming assay. Results Microscopic and flow cytometric analysis revealed the erythroid differentiation of CD133+cord blood HSCs under applied erythroid inducing conditions. Our flow cytometric data showed that the TfR and GPA positive cell population diminished significantly in the presence of either troglitazone or baicalin. The suppression of erythroid differentiation in response to PPARγ agonists was dose-dependent. Erythroid colony-forming ability of HSC decreased significantly after treatment with both PPARγ agonists but troglitazone had a markedly greater effect. Conclusion Our results have demonstrated that PPARγ agonists modulate erythroid dif- ferentiation of CD133+HSCs, and therefore play an important role in regulation of normal erythropoiesis under physiologic conditions. Thus, considering the availability and applica

  19. Increase of microRNA-210, Decrease of Raptor Gene Expression and Alteration of Mammalian Target of Rapamycin Regulated Proteins following Mithramycin Treatment of Human Erythroid Cells

    PubMed Central

    Bianchi, Nicoletta; Finotti, Alessia; Ferracin, Manuela; Lampronti, Ilaria; Zuccato, Cristina; Breveglieri, Giulia; Brognara, Eleonora; Fabbri, Enrica; Borgatti, Monica; Negrini, Massimo; Gambari, Roberto

    2015-01-01

    Expression and regulation of microRNAs is an emerging issue in erythroid differentiation and globin gene expression in hemoglobin disorders. In the first part of this study microarray analysis was performed both in mithramycin-induced K562 cells and erythroid precursors from healthy subjects or β-thalassemia patients producing low or high levels of fetal hemoglobin. We demonstrated that: (a) microRNA-210 expression is higher in erythroid precursors from β-thalassemia patients with high production of fetal hemoglobin; (b) microRNA-210 increases as a consequence of mithramycin treatment of K562 cells and human erythroid progenitors both from healthy and β-thalassemia subjects; (c) this increase is associated with erythroid induction and elevated expression of γ-globin genes; (d) an anti-microRNA against microRNA-210 interferes with the mithramycin-induced changes of gene expression. In the second part of the study we have obtained convergent evidences suggesting raptor mRNA as a putative target of microRNA-210. Indeed, microRNA-210 binding sites of its 3’-UTR region were involved in expression and are targets of microRNA-210-mediated modulation in a luciferase reporter assays. Furthermore, (i) raptor mRNA and protein are down-regulated upon mithramycin-induction both in K562 cells and erythroid progenitors from healthy and β-thalassemia subjects. In addition, (ii) administration of anti-microRNA-210 to K562 cells decreased endogenous microRNA-210 and increased raptor mRNA and protein expression. Finally, (iii) treatment of K562 cells with premicroRNA-210 led to a decrease of raptor mRNA and protein. In conclusion, microRNA-210 and raptor are involved in mithramycin-mediated erythroid differentiation of K562 cells and participate to the fine-tuning and control of γ-globin gene expression in erythroid precursor cells. PMID:25849663

  20. The DEK Oncoprotein Is a Critical Component of the EKLF/KLF1 Enhancer in Erythroid Cells

    PubMed Central

    Lohmann, Felix; Dangeti, Mohan; Soni, Shefali; Chen, Xiaoyong; Planutis, Antanas; Baron, Margaret H.; Choi, Kyunghee

    2015-01-01

    Understanding how transcriptional regulators are themselves controlled is important in attaining a complete picture of the intracellular effects that follow signaling cascades during early development and cell-restricted differentiation. We have addressed this issue by focusing on the regulation of EKLF/KLF1, a zinc finger transcription factor that plays a necessary role in the global regulation of erythroid gene expression. Using biochemical affinity purification, we have identified the DEK oncoprotein as a critical factor that interacts with an essential upstream enhancer element of the EKLF promoter and exerts a positive effect on EKLF levels. This element also binds a core set of erythroid transcription factors, suggesting that DEK is part of a tissue-restricted enhanceosome that contains BMP4-dependent and -independent components. Together with local enrichment of properly coded histones and an open chromatin domain, optimal transcriptional activation of the EKLF locus can be established. PMID:26303528

  1. Evaluation of hematopoietic cells and myeloid/erythroid ratio in the bone marrow of the pheasant (Phasianus colchicus).

    PubMed

    Tadjalli, Mina; Nazifi, Saeed; Haghjoo, Rahil

    2013-01-01

    In order to study the normal hematopoiesis, cellular components and myeloid/erythroid (M/E) ratio in the bone marrow of the pheasant (Phasianus colchicus), bone marrow samples were collected from the proximal tibiotarsus bone of 16 clinically healthy adult pheasant. The bone marrow smears were stained using the Giemsa stain. The results indicated that the development and formation of blood cells in the bone marrow of pheasant were similar to other birds, whereas the morphology of the cells was similar to chickens, ducks, quail, and black-head gull. The mean M/E ratio was 1.24, the mean erythroid percentage was 42.24, the mean myeloid percentage was 52.62, and the mean percentage of all other cells percentage was 5.38. There was no significant difference in any of the cellular composition between male and female. PMID:25653783

  2. TRPC3 is the erythropoietin-regulated calcium channel in human erythroid cells.

    PubMed

    Tong, Qin; Hirschler-Laszkiewicz, Iwona; Zhang, Wenyi; Conrad, Kathleen; Neagley, David W; Barber, Dwayne L; Cheung, Joseph Y; Miller, Barbara A

    2008-04-18

    Erythropoietin (Epo) stimulates a significant increase in the intracellular calcium concentration ([Ca(2+)](i)) through activation of the murine transient receptor potential channel TRPC2, but TRPC2 is a pseudogene in humans. TRPC3 expression increases on normal human erythroid progenitors during differentiation. Here, we determined that erythropoietin regulates calcium influx through TRPC3. Epo stimulation of HEK 293T cells transfected with Epo receptor and TRPC3 resulted in a dose-dependent increase in [Ca(2+)](i), which required extracellular calcium influx. Treatment with the phospholipase C (PLC) inhibitor U-73122 or down-regulation of PLCgamma1 by RNA interference inhibited the Epo-stimulated increase in [Ca(2+)](i) in TRPC3-transfected HEK 293T cells and in primary human erythroid precursors, demonstrating a requirement for PLC. TRPC3 associated with PLCgamma, and substitution of predicted PLCgamma Src homology 2 binding sites (Y226F, Y555F, Y648F, and Y674F) on TRPC3 reduced the interaction of TRPC3 with PLCgamma and inhibited the rise in [Ca(2+)](i). Substitution of Tyr(226) alone with phenylalanine significantly reduced the Epo-stimulated increase in [Ca(2+)](i) but not the association of PLCgamma with TRPC3. PLC activation results in production of inositol 1,4,5-trisphosphate (IP(3)). To determine whether IP(3) is involved in Epo activation of TRPC3, TRPC3 mutants were prepared with substitution or deletion of COOH-terminal IP(3) receptor (IP(3)R) binding domains. In cells expressing TRPC3 with mutant IP(3)R binding sites and Epo receptor, interaction of IP(3)R with TRPC3 was abolished, and Epo-modulated increase in [Ca(2+)](i) was reduced. Our data demonstrate that Epo modulates TRPC3 activation through a PLCgamma-mediated process that requires interaction of PLCgamma and IP(3)R with TRPC3. They also show that TRPC3 Tyr(226) is critical in Epo-dependent activation of TRPC3. These data demonstrate a redundancy of TRPC channel activation mechanisms by

  3. Transcription factor nuclear factor erythroid-2 mediates expression of the cytokine interleukin 8, a known predictor of inferior outcome in patients with myeloproliferative neoplasms

    PubMed Central

    Wehrle, Julius; Seeger, Thalia S.; Schwemmers, Sven; Pfeifer, Dietmar; Bulashevska, Alla; Pahl, Heike L.

    2013-01-01

    The transcription factor nuclear factor erythroid-2 is over-expressed in patients with myeloproliferative neoplasms irrespective of the presence of the JAK2V617F mutation. Our transgenic mouse model over-expressing nuclear factor erythroid-2, which recapitulates many features of myeloproliferative neoplasms including transformation to acute myeloid leukemia, clearly implicates this transcription factor in the pathophysiology of myeloproliferative neoplasms. Because the targets mediating nuclear factor erythroid-2 effects are not well characterized, we conducted microarray analysis of CD34+ cells lentivirally transduced to over-express nuclear factor erythroid-2 or to silence this transcription factor via shRNA, in order to identify novel target genes. Here, we report that the cytokine interleukin 8 is a novel target gene. Nuclear factor erythroid-2 directly binds the interleukin 8 promoter in vivo, and these binding sites are required for promoter activity. Serum levels of interleukin 8 are known to be elevated in both polycythemia vera and primary myelofibrosis patients. Recently, increased interleukin 8 levels have been shown to be predictive of inferior survival in primary myelofibrosis patients in multivariate analysis. Therefore, one of the mechanisms by which nuclear factor erythroid-2 contributes to myeloproliferative neoplasm pathology may be increased interleukin 8 expression. PMID:23445878

  4. Dissection of the erythroid-specific transcriptional promoter used by the gene encoding aminolevulinic acid dehydratase (ALAD)

    SciTech Connect

    Bishop, T.R.; Schaffer, T.; Pien, B.

    1994-09-01

    The gene encoding delta-aminolevulinate dehydratase (ALAD), the second enzyme of the heme biosynthetic pathway, exists as a single gene in most mammalian genomes and we have sequenced over 12 kb from overlapping lambda clones containing the murine ALAD gene. The gene has a dual promoter driving expression of two different first exons; exon1A is expressed in all tissues and exon1B only in erythroid cells, where heme production is induced to exceptionally high levels for hemoglobin synthesis. Erythroid-specific expression of the ALAD gene is presumably accomplished by using the exon1B promoter which we hypothesize is responsive to erythroid-specific transcriptional activators. In order to test this, we have used gel mobility shift assays and DNase footprint analyses to dissect and identify the critical upstream regulatory elements. Nuclear extracts, prepared from murine erythroleukemia cells (MELC), human chronic myelogenous leukemia cell line (K562) and human fibroblast cell line (HeLa), were used as sources of proteins to analyze DNA binding sites in the ALAD erythroid-specific promoter from -307 to +1. In this region, there are three potential GATA1 sites, two CACCC boxes, a CCAAT box and a GGTGG box. NF-E2 sites were explored by using in vitro translation products of cloned p18 and p45, the two heterologous components of NF-E2, and successfully gel-shifted a 29 bp double-stranded oligo found at 2.6 kb in front of the ALAD gene. Thus, the ALAD gene utilizes both a housekeeping and a tissue-specific promoter.

  5. Murine erythroid 5-aminolevulinate synthase: Truncation of a disordered N-terminal extension is not detrimental for catalysis.

    PubMed

    Stojanovski, Bosko M; Breydo, Leonid; Uversky, Vladimir N; Ferreira, Gloria C

    2016-05-01

    5-Aminolevulinate synthase (ALAS), a pyridoxal 5'-phosphate (PLP)-dependent homodimeric enzyme, catalyzes the initial step of heme biosynthesis in non-plant eukaryotes. The precursor form of the enzyme is translated in the cytosol, and upon mitochondrial import, the N-terminal targeting presequence is proteolytically cleaved to generate mature ALAS. In bone marrow-derived erythroid cells, a mitochondrial- and site-specific endoprotease of yet unknown primary structure, produces a protein shorter than mature erythroid ALAS (ALAS2) found in peripheral blood erythroid cells. This truncated ALAS2 lacks the presequence and the N-terminal sequence (corresponding to ~7 KDa molecular mass) present in ALAS2 from peripheral blood erythroid cells. How the truncation affects the structural topology and catalytic properties of ALAS2 is presently not known. To address this question, we created a recombinant, truncated, murine ALAS2 (ΔmALAS2) devoid of the cleavable N-terminal region and examined its catalytic and biophysical properties. The N-terminal truncation of mALAS2 did not significantly affect the organization of the secondary structure, but a subtle reduction in the rigidity of the tertiary structure was noted. Furthermore, thermal denaturation studies revealed a decrease of 4.3°C in the Tm value of ΔmALAS2, implicating lower thermal stability. While the kcat of ΔmALAS2 is slightly increased over that of the wild-type enzyme, the slowest step in the ΔmALAS2-catalyzed reaction remains dominated by ALA release. Importantly, intrinsic disorder algorithms imply that the N-terminal region of mALAS2 is highly disordered, and thus susceptible to proteolysis. We propose that the N-terminal truncation offers a cell-specific ALAS2 regulatory mechanism without hindering heme synthesis. PMID:26854603

  6. Complex patterns of sequence variation and multiple 5' and 3' ends are found among transcripts of the erythroid ankyrin gene.

    PubMed

    Birkenmeier, C S; White, R A; Peters, L L; Hall, E J; Lux, S E; Barker, J E

    1993-05-01

    The structural protein ankyrin functions in red blood cells to link the spectrin-based membrane skeleton to the plasma membrane. Ankyrin proteins are now known to occur in most cell types, and two distinct ankyrin genes have been identified (erythroid (Ank-1) and brain (Ank-2)). We have characterized transcripts of the mouse erythroid ankyrin gene by cDNA cloning and DNA sequencing. Ank-1 transcripts of 7.5 and 9.0 kilobases are found in erythroid tissues, and a 9.0-kilobase transcript is found in cerebellum. RNA hybridization blot analysis of 13 additional mouse tissues has detected four novel Ank-1 transcripts (5.0, 3.5, 2.0, and 1.6 kilobases in size). Sequencing of Ank-1 cDNA clones isolated from mouse reticulocyte, spleen, and cerebellar libraries has identified (i) multiple 5' ends that indicate possible multiple promoters; (ii) alternative polyadenylation sites that probably account for the 7.5- and 9.0-kilobase size difference; (iii) a variety of small insertions and deletions that could produce transcripts (and ultimately proteins) of nearly identical size, but different functions; and (iv) clones with large deletions of coding sequence that account for the smaller transcripts seen in spleen, skeletal muscle, and heart. PMID:8486643

  7. Glucocorticoids improve erythroid progenitor maintenance and dampen Trp53 response in a mouse model of Diamond-Blackfan anaemia.

    PubMed

    Sjögren, Sara E; Siva, Kavitha; Soneji, Shamit; George, Amee J; Winkler, Marcus; Jaako, Pekka; Wlodarski, Marcin; Karlsson, Stefan; Hannan, Ross D; Flygare, Johan

    2015-11-01

    Diamond-Blackfan anaemia (DBA) is a rare congenital disease causing severe anaemia and progressive bone marrow failure. The majority of patients carry mutations in ribosomal proteins, which leads to depletion of erythroid progenitors in the bone marrow. As many as 40% of all DBA patients receive glucocorticoids to alleviate their anaemia. However, despite their use in DBA treatment for more than half a century, the therapeutic mechanisms of glucocorticoids remain largely unknown. Therefore we sought to study disease specific effects of glucocorticoid treatment using a ribosomal protein s19 (Rps19) deficient mouse model of DBA. This study determines for the first time that a mouse model of DBA can respond to glucocorticoid treatment, similar to DBA patients. Our results demonstrate that glucocorticoid treatment reduces apoptosis, rescues erythroid progenitor depletion and premature differentiation of erythroid cells. Furthermore, glucocorticoids prevent Trp53 activation in Rps19-deficient cells- in a disease-specific manner. Dissecting the therapeutic mechanisms behind glucocorticoid treatment of DBA provides indispensible insight into DBA pathogenesis. Identifying mechanisms important for DBA treatment also enables development of more disease-specific treatments of DBA. PMID:26305041

  8. Tissue specific transcription of the human epsilon-globin gene following transfection into the embryonic erythroid cell line K562.

    PubMed Central

    Allan, M; Montague, P; Grindlay, G J; Sibbet, G; Donovan-Peluso, M; Bank, A; Paul, J

    1985-01-01

    We have introduced a plasmid containing the human epsilon-globin gene either stably or transiently into a number of erythroid or non-erythroid cell lines, and analysed the accuracy and efficiency of transcription. In non-erythroid cells (or in mouse erythroleukaemia (MEL) cells in which adult but not embryonic globin genes are expressed) transcription of the epsilon-globin gene occurs mainly from a site 200 bp upstream of the major cap site (the -200 cap site). In the human K562 cell line, in which the endogenous epsilon-globin gene is transcribed at high levels, transcription initiation from the introduced gene occurs mainly from the major cap site. Transcriptional activity of the epsilon-globin gene introduced into K562 cell is quantitatively similar to that of the endogenous gene. This suggests the presence (or absence) in K562 cells of factor(s) which activate (or repress) the epsilon-globin gene in a tissue specific manner. Images PMID:2995916

  9. [Short-term curative effect of amifostine combined with rhbeta-EPO on patients with pure erythroid aplasia].

    PubMed

    Li, Su-Xia; Zhu, Hong-Li; Lu, Xue-Chun; Fan, Hui; Guo, Bo; Zhai, Bing

    2008-10-01

    The aim of this study was to investigate the curative effects of amifostine (AMF) combined with recombinant human beta-erythropoietin (rhbeta-EPO) on patients with pure erythroid aplasia (PEA). Two patients with PEA were treated with amifostine and rhbeta-EPO. The therapeutic regimen was adopted with AMF 0.4 g/day given by intravenous injection for 5 days first, then after a break of 2 days it went on for 3 weeks consecutively, that was considered as one treatment cycle. The rhbeta-EPO 6 000 U was used by subcutaneous injection for 3 times per week. The results showed that the red cell count, hemoglobin and reticulocyte count of two patients obviously increased after treatment. The erythroid ratio in bone marrow increased. Bone marrow biopsy showed that the erythroid proliferation improved. Intervals of red cell transfusions (RCT) in the two patients who live by red cell transfusion were prolonged after AMF treatments, and the amounts of each RCT was decreased obviously. The main side effect of amifostine was discomfort of digestive system, but was tolerated by all patients. In conclusion, amifostine plus rhbeta-EPO may be a new, effective and safety method especially for the elder PEA patients. The long-term curative effects and mechanism of amifostine still need further evaluation. PMID:18928605

  10. Inactivation of Rb and E2f8 Synergizes To Trigger Stressed DNA Replication during Erythroid Terminal Differentiation

    PubMed Central

    Ghazaryan, Seda; Sy, Chandler; Hu, Tinghui; An, Xiuli; Mohandas, Narla; Fu, Haiqing; Aladjem, Mirit I.; Chang, Victor T.; Opavsky, Rene

    2014-01-01

    Rb is critical for promoting cell cycle exit in cells undergoing terminal differentiation. Here we show that during erythroid terminal differentiation, Rb plays a previously unappreciated and unorthodox role in promoting DNA replication and cell cycle progression. Specifically, inactivation of Rb in erythroid cells led to stressed DNA replication, increased DNA damage, and impaired cell cycle progression, culminating in defective terminal differentiation and anemia. Importantly, all of these defects associated with Rb loss were exacerbated by the concomitant inactivation of E2f8. Gene expression profiling and chromatin immunoprecipitation (ChIP) revealed that Rb and E2F8 cosuppressed a large array of E2F target genes that are critical for DNA replication and cell cycle progression. Remarkably, inactivation of E2f2 rescued the erythropoietic defects resulting from Rb and E2f8 deficiencies. Interestingly, real-time quantitative PCR (qPCR) on E2F2 ChIPs indicated that inactivation of Rb and E2f8 synergizes to increase E2F2 binding to its target gene promoters. Taken together, we propose that Rb and E2F8 collaborate to promote DNA replication and erythroid terminal differentiation by preventing E2F2-mediated aberrant transcriptional activation through the ability of Rb to bind and sequester E2F2 and the ability of E2F8 to compete with E2F2 for E2f-binding sites on target gene promoters. PMID:24865965

  11. Sustainable weight loss among overweight and obese lactating women is achieved with an energy-reduced diet in line with dietary recommendations: results from the LEVA randomized controlled trial.

    PubMed

    Bertz, Fredrik; Winkvist, Anna; Brekke, Hilde K

    2015-01-01

    The aim of this study was to evaluate dietary changes during and after a dietary treatment shown to result in significant and sustained weight loss among lactating overweight and obese women. This is crucial before clinical implementation. Data were collected from the LEVA (in Swedish: Livsstil för Effektiv Viktminskning under Amning [Lifestyle for Effective Weight Loss During Lactation]) randomized controlled factorial trial with a 12-week intervention and a 1-year follow up. At 10 to 14 weeks postpartum, 68 lactating Swedish women with a prepregnancy body mass index (calculated as kg/m(2)) of 25 to 35 were randomized to structured dietary treatment, physical exercise treatment, combined treatment, or usual care (controls) for a 12-week intervention, with a 1-year follow-up. Dietary intake was assessed with 4-day weighed dietary records. Recruitment took place between 2007 and 2010. The main outcome measures were changes in macro- and micronutrient intake from baseline to 12 weeks and 1 year. Main and interaction effects of the treatments were analyzed by a 2×2 factorial approach using a General Linear Model adjusted for relevant covariates (baseline intake and estimated underreporting). It was found that at baseline, the women had an intake of fat and sucrose above, and an intake of total carbohydrates and fiber below, recommended levels. At 12 weeks and 1 year, the dietary treatment led to reduced intake of energy (P<0.001 and P=0.005, respectively), fat (both P values <0.001), and sucrose (P<0.001 and P=0.050). At 12 weeks, total carbohydrates were reduced (P<0.001). A majority of women in all groups reported low intakes of vitamin D, folate, and/or iron. In conclusion, a novel dietary treatment led to reduced intake of fat and carbohydrates. Diet composition changed to decreased proportions of fat and sucrose, and increased proportions of complex carbohydrates, protein and fiber. Weight loss through dietary treatment was achieved with a diet in line with

  12. Nuclear Factor Erythroid 2-Related Factor 2 Drives Podocyte-Specific Expression of Peroxisome Proliferator-Activated Receptor γ Essential for Resistance to Crescentic GN.

    PubMed

    Henique, Carole; Bollee, Guillaume; Lenoir, Olivia; Dhaun, Neeraj; Camus, Marine; Chipont, Anna; Flosseau, Kathleen; Mandet, Chantal; Yamamoto, Masayuki; Karras, Alexandre; Thervet, Eric; Bruneval, Patrick; Nochy, Dominique; Mesnard, Laurent; Tharaux, Pierre-Louis

    2016-01-01

    Necrotizing and crescentic rapidly progressive GN (RPGN) is a life-threatening syndrome characterized by a rapid loss of renal function. Evidence suggests that podocyte expression of the transcription factor peroxisome proliferator-activated receptor γ (PPARγ) may prevent podocyte injury, but the function of glomerular PPARγ in acute, severe inflammatory GN is unknown. Here, we observed marked loss of PPARγ abundance and transcriptional activity in glomerular podocytes in experimental RPGN. Blunted expression of PPARγ in podocyte nuclei was also found in kidneys from patients diagnosed with crescentic GN. Podocyte-specific Pparγ gene targeting accentuated glomerular damage, with increased urinary loss of albumin and severe kidney failure. Furthermore, a PPARγ gain-of-function approach achieved by systemic administration of thiazolidinedione (TZD) failed to prevent severe RPGN in mice with podocyte-specific Pparγ gene deficiency. In nuclear factor erythroid 2-related factor 2 (NRF2)-deficient mice, loss of podocyte PPARγ was observed at baseline. NRF2 deficiency markedly aggravated the course of RPGN, an effect that was partially prevented by TZD administration. Furthermore, delayed administration of TZD, initiated after the onset of RPGN, still alleviated the severity of experimental RPGN. These findings establish a requirement for the NRF2-PPARγ cascade in podocytes, and we suggest that these transcription factors have a role in augmenting the tolerance of glomeruli to severe immune-complex mediated injury. The NRF2-PPARγ pathway may be a therapeutic target for RPGN. PMID:25999406

  13. Krüppel-like Factor 4 activates HBG gene expression in primary erythroid cells

    PubMed Central

    Kalra, Inderdeep S.; Alam, Md M.; Choudhary, Pankaj K.; Pace, Betty S.

    2014-01-01

    Summary The SP1/Krüppel-like Factor (SP1/KLF) family of transcription factors plays a role in diverse cellular processes, including proliferation, differentiation and control of gene transcription. The discovery of KLF1 (EKLF), a key regulator of HBB (β-globin) gene expression, expanded our understanding of the role of KLFs in erythropoiesis. In this study, we investigated a mechanism of HBG (γ-globin) regulation by KLF4. siRNA-mediated gene silencing and enforced expression of KLF4 in K562 cells substantiated the ability of KLF4 to positively regulate endogenous HBG gene transcription. The physiological significance of this finding was confirmed in primary erythroid cells, where KLF4 knockdown at day 11 significantly attenuated HBG mRNA levels and enforced expression at day 28 stimulated the silenced HBG genes. In vitro binding characterization using the γ-CACCC and β-CACCC probes demonstrated KLF4 preferentially binds the endogenous γ-CACCC, while CREB binding protein (CREBBP) binding was not selective. Co-immunoprecipitation studies confirmed protein-protein interaction between KLF4 and CREBBP. Furthermore, sequential chromatin immunoprecipitation assays showed co-localization of both factors in the γ-CACCC region. Subsequent luciferase reporter studies demonstrated that KLF4 trans-activated HBG promoter activity and that CREBBP enforced expression resulted in gene repression. Our data supports a model of antagonistic interaction of KLF4/CREBBP trans-factors in HBG regulation. PMID:21539536

  14. Nuclear factor, erythroid 2-like 2-associated molecular signature predicts lung cancer survival

    PubMed Central

    Qian, Zhongqing; Zhou, Tong; Gurguis, Christopher I.; Xu, Xiaoyan; Wen, Qing; Lv, Jingzhu; Fang, Fang; Hecker, Louise; Cress, Anne E.; Natarajan, Viswanathan; Jacobson, Jeffrey R.; Zhang, Donna D.; Garcia, Joe G. N.; Wang, Ting

    2015-01-01

    Nuclear factor, erythroid 2-like 2 (NFE2L2), a transcription factor also known as NF-E2-related factor 2 (Nrf2), is a key cytoprotective gene that regulates critical antioxidant and stress-responsive genes. Nrf2 has been demonstrated to be a promising therapeutic target and useful biomarker in malignant disease. We hypothesized that NFE2L2-mediated gene expression would reflect cancer severity and progression. We conducted a meta-analysis of microarray data for 240 NFE2L2-mediated genes that were enriched in tumor tissues. We then developed a risk scoring system based on NFE2L2 gene expression profiling and designated 50 tumor-associated genes as the NFE2L2-associated molecular signature (NAMS). We tested the relationship between this gene expression signature and both recurrence-free survival and overall survival in lung cancer patients. We find that NAMS predicts clinical outcome in the training cohort and in 12 out of 20 validation cohorts. Cox proportional hazard regressions indicate that NAMS is a robust prognostic gene signature, independent of other clinical and pathological factors including patient age, gender, smoking, gene alteration, MYC level, and cancer stage. NAMS is an excellent predictor of recurrence-free survival and overall survival in human lung cancer. This gene signature represents a promising prognostic biomarker in human lung cancer. PMID:26596768

  15. Therapeutic fetal-globin inducers reduce transcriptional repression in hemoglobinopathy erythroid progenitors through distinct mechanisms.

    PubMed

    Dai, Yan; Sangerman, Jose; Luo, Hong Yuan; Fucharoen, Suthat; Chui, David H K; Faller, Douglas V; Perrine, Susan P

    2016-01-01

    Pharmacologic augmentation of γ-globin expression sufficient to reduce anemia and clinical severity in patients with diverse hemoglobinopathies has been challenging. In studies here, representative molecules from four chemical classes, representing several distinct primary mechanisms of action, were investigated for effects on γ-globin transcriptional repressors, including components of the NuRD complex (LSD1 and HDACs 2-3), and the downstream repressor BCL11A, in erythroid progenitors from hemoglobinopathy patients. Two HDAC inhibitors (MS-275 and SB939), a short-chain fatty acid derivative (sodium dimethylbutyrate [SDMB]), and an agent identified in high-throughput screening, Benserazide, were studied. These therapeutics induced γ-globin mRNA in progenitors above same subject controls up to 20-fold, and increased F-reticulocytes up to 20%. Cellular protein levels of BCL11A, LSD-1, and KLF1 were suppressed by the compounds. Chromatin immunoprecipitation assays demonstrated a 3.6-fold reduction in LSD1 and HDAC3 occupancy in the γ-globin gene promoter with Benserazide exposure, 3-fold reduction in LSD-1 and HDAC2 occupancy in the γ-globin gene promoter with SDMB exposure, while markers of gene activation (histone H3K9 acetylation and H3K4 demethylation), were enriched 5.7-fold. These findings identify clinical-stage oral therapeutics which inhibit or displace major co-repressors of γ-globin gene transcription and may suggest a rationale for combination therapy to produce enhanced efficacy. PMID:26603726

  16. Inducible Gata1 suppression expands megakaryocyte-erythroid progenitors from embryonic stem cells

    PubMed Central

    Noh, Ji-Yoon; Gandre-Babbe, Shilpa; Wang, Yuhuan; Hayes, Vincent; Yao, Yu; Gadue, Paul; Sullivan, Spencer K.; Chou, Stella T.; Machlus, Kellie R.; Italiano, Joseph E.; Kyba, Michael; Finkelstein, David; Ulirsch, Jacob C.; Sankaran, Vijay G.; French, Deborah L.; Poncz, Mortimer; Weiss, Mitchell J.

    2015-01-01

    Transfusion of donor-derived platelets is commonly used for thrombocytopenia, which results from a variety of clinical conditions and relies on a constant donor supply due to the limited shelf life of these cells. Embryonic stem (ES) and induced pluripotent stem (iPS) cells represent a potential source of megakaryocytes and platelets for transfusion therapies; however, the majority of current ES/iPS cell differentiation protocols are limited by low yields of hematopoietic progeny. In both mice and humans, mutations in the gene-encoding transcription factor GATA1 cause an accumulation of proliferating, developmentally arrested megakaryocytes, suggesting that GATA1 suppression in ES and iPS cell–derived hematopoietic progenitors may enhance megakaryocyte production. Here, we engineered ES cells from WT mice to express a doxycycline-regulated (dox-regulated) shRNA that targets Gata1 transcripts for degradation. Differentiation of these cells in the presence of dox and thrombopoietin (TPO) resulted in an exponential (at least 1013-fold) expansion of immature hematopoietic progenitors. Dox withdrawal in combination with multilineage cytokines restored GATA1 expression, resulting in differentiation into erythroblasts and megakaryocytes. Following transfusion into recipient animals, these dox-deprived mature megakaryocytes generated functional platelets. Our findings provide a readily reproducible strategy to exponentially expand ES cell–derived megakaryocyte-erythroid progenitors that have the capacity to differentiate into functional platelet-producing megakaryocytes. PMID:25961454

  17. Erythropoietin, a Novel Versatile Player Regulating Energy Metabolism beyond the Erythroid System

    PubMed Central

    Wang, Li; Di, Lijun; Noguchi, Constance Tom

    2014-01-01

    Erythropoietin (EPO), the required cytokine for promoting the proliferation and differentiation of erythroid cells to stimulate erythropoiesis, has been reported to act as a pleiotropic cytokine beyond hematopoietic system. The various activities of EPO are determined by the widespread distribution of its cell surface EPO receptor (EpoR) in multiple tissues including endothelial, neural, myoblasts, adipocytes and other cell types. EPO activity has been linked to angiogenesis, neuroprotection, cardioprotection, stress protection, anti-inflammation and especially the energy metabolism regulation that is recently revealed. The investigations of EPO activity in animals and the expression analysis of EpoR provide more insights on the potential of EPO in regulating energy metabolism and homeostasis. The findings of crosstalk between EPO and some important energy sensors and the regulation of EPO in the cellular respiration and mitochondrial function further provide molecular mechanisms for EPO activity in metabolic activity regulation. In this review, we will summarize the roles of EPO in energy metabolism regulation and the activity of EPO in tissues that are tightly associated with energy metabolism. We will also discuss the effects of EPO in regulating oxidative metabolism and mitochondrial function, the interactions between EPO and important energy regulation factors, and the protective role of EPO from stresses that are related to metabolism, providing a brief overview of previously less appreciated EPO biological function in energy metabolism and homeostasis. PMID:25170305

  18. The structure and organization of the human erythroid anion exchanger (AE1) gene

    SciTech Connect

    Sahr, K.E.; Taylor, W.M.; Daniels, B.P.

    1994-12-01

    The AE1 (anion exchanger, band 3) protein is expressed in erythrocytes and in the A-type intercalated cells of the kidney distal collecting tubule. In both cell types it mediates the electroneutral transport of chloride and bicarbonate ions across the lipid bilayer, and, in erythrocytes, it also serves as the critical attachment site of the peripheral membrane skeleton. We have characterized the human AE1 gene using overlapping clones isolated from a phage library of human genomic DNA. The gene spans {approximately}20 kb and consists of 20 exons separated by 19 introns. The structure of the human AE1 gene corresponds closely with that of the previously characterized mouse AE1 gene, with a high degree of conservation of exon/intron junctions, as well as exon and intron nucleotide sequences. The putative upstream and internal promoter sequences of the human AE1 gene used in erythroid and kidney cells, respectively, are described. We also report the nucleotide sequence of the entire 3{prime} noncoding region of exon 20, which was lacking in the published cDNA sequences. In addition, we have characterized 9 Alu repeat elements found within the body of the human AE1 gene that are members of 4 related subfamilies that appear to have entered the genome at different times during primate evolution. 59 refs., 5 figs., 2 tabs.

  19. Nuclear factor, erythroid 2-like 2-associated molecular signature predicts lung cancer survival.

    PubMed

    Qian, Zhongqing; Zhou, Tong; Gurguis, Christopher I; Xu, Xiaoyan; Wen, Qing; Lv, Jingzhu; Fang, Fang; Hecker, Louise; Cress, Anne E; Natarajan, Viswanathan; Jacobson, Jeffrey R; Zhang, Donna D; Garcia, Joe G N; Wang, Ting

    2015-01-01

    Nuclear factor, erythroid 2-like 2 (NFE2L2), a transcription factor also known as NF-E2-related factor 2 (Nrf2), is a key cytoprotective gene that regulates critical antioxidant and stress-responsive genes. Nrf2 has been demonstrated to be a promising therapeutic target and useful biomarker in malignant disease. We hypothesized that NFE2L2-mediated gene expression would reflect cancer severity and progression. We conducted a meta-analysis of microarray data for 240 NFE2L2-mediated genes that were enriched in tumor tissues. We then developed a risk scoring system based on NFE2L2 gene expression profiling and designated 50 tumor-associated genes as the NFE2L2-associated molecular signature (NAMS). We tested the relationship between this gene expression signature and both recurrence-free survival and overall survival in lung cancer patients. We find that NAMS predicts clinical outcome in the training cohort and in 12 out of 20 validation cohorts. Cox proportional hazard regressions indicate that NAMS is a robust prognostic gene signature, independent of other clinical and pathological factors including patient age, gender, smoking, gene alteration, MYC level, and cancer stage. NAMS is an excellent predictor of recurrence-free survival and overall survival in human lung cancer. This gene signature represents a promising prognostic biomarker in human lung cancer. PMID:26596768

  20. Therapeutic Effects of Erythroid Differentiation Regulator 1 on Imiquimod-Induced Psoriasis-Like Skin Inflammation

    PubMed Central

    Kim, Kyung Eun; Houh, Younkyung; Park, Hyun Jeong; Cho, Daeho

    2016-01-01

    Psoriasis is a common skin disease accompanied by chronic inflammation. In previous studies, erythroid differentiation regulator 1 (ERDR1) was shown to have a negative correlation with proinflammatory cytokine IL-18. However, the role of ERDR1 in the inflammatory skin disease psoriasis has not been evaluated. In this study, to investigate the role of ERDR1 in psoriasis, recombinant ERDR1 was injected intraperitoneally into a psoriasis mouse model. Recombinant ERDR1 (rERDR1) significantly alleviated the symptoms of psoriasis-like skin inflammation and reduced the mRNA of various psoriasis-related markers, including keratin 14, S100A8, and Th17-related cytokines IL-17 and IL-22, suggesting that rERDR1 exerts therapeutic effects on psoriasis via the regulation of Th17 functions. Additionally, the expression of CCL20, a well-known Th17 attracting chemokine, was determined. CCL20 expression significantly decreased in the rERDR1-injected group compared with the vehicle (PBS)-injected group. CCR6 expression in the psoriatic lesional skin was also decreased by rERDR1 administration, implying the inhibition of CCR6-expressing Th17 cell chemotaxis via the downregulation of CCL20. Taken together, this study provides the first evidence that ERDR1 may be a potential therapeutic target for psoriasis. PMID:26901187

  1. FOXP1 Expression in Normal and Neoplastic Erythroid and Myeloid Cells.

    PubMed

    Lovrić, Eva; Pavlov, Katarina Horvat; Korać, Petra; Dominis, Mara

    2015-09-01

    FOXP1 protein was firstly analyzed in normal tissues, and afterwards in different tumor tissues, mainly carcinoma and lymphoma. In B-cell malignancies, its role was well explored; its expression was shown to be connected with disease prognosis in certain B-non Hodgkin lymphomas. In this study, 16 bone marrow trephine samples from patients with no hematopoietic malignancies and 10 samples from peripheral blood of healthy individuals were immunostained with anti-FOXP1 antibody. Positive cells in bone marrows were not only lymphocytes, but also cells that are immunohistochemically positive for glycophorin C or myeloperoxidase. Peripheral blood samples showed no other positive cells, but small round lymphocytes. Additionally 60 samples from patients with myeloid lineage neoplasms were analyzed. 25 samples from patients with myelodysplastic syndrome (MDS) and 35 patients with myeloproliferative disease (MPD) were double immunostained with anti-FOXP1/anti-glycophorin C and anti-FOXP1/anti-myeloperoxidase antibodies. FOXP1 was found to be expressed in 22 cases of MDS and in none of MPD cases. Its expression in MDS was observed mostly in myeloperoxidase positive cells in contrast to gylcophorin C positive cells. Only two cases revealed both myeloperoxidase positive cells and gylcophorin C positive cells expressing FOXP1 transcription factor. Our results show that FOXP1 is present in normal cells of erythroid and myeloid linages and thus suggest its possible role in development of all hematopoetic cells as well as possible involvement in neoplasm development of myeloid disorders. PMID:26898077

  2. Perturbation of nucleosome structure by the erythroid transcription factor GATA-1.

    PubMed

    Boyes, J; Omichinski, J; Clark, D; Pikaart, M; Felsenfeld, G

    1998-06-12

    The ability of transcription factors to gain access to their sites in chromatin requires the disruption or displacement of nucleosomes covering the promoter, signalled by the generation of a nuclease hypersensitive site. We characterise here the alterations in nucleosome structure caused by binding of the erythroid factor GATA-1 to a nucleosome carrying GATA-1 sites. DNase I and micrococcal nuclease probes show that GATA-1 binding causes extensive, cooperative breakage of the histone/DNA contacts to generate a complex very similar to that formed by the factor with free DNA. The only region which differs is confined to about 50 bp surrounding the nucleosome dyad axis which appears to be the domain of residual contact between the DNA and histone octamer. Despite considerable breakage of the histone/DNA contacts, the complex is completely stable in solution, and disruption of the nucleosome is entirely reversible: it is regenerated quantitatively upon removal of the transcription factor. Moreover, the histone 2A/2B component of the octamer does not exchange to external competitor. We suggest that formation of this complex may be a step in the generation of a fully hypersensitive site in vivo over regulatory elements containing GATA family binding sites. PMID:9641976

  3. Acute megakaryoblastic leukemia, unlike acute erythroid leukemia, predicts an unfavorable outcome after allogeneic HSCT.

    PubMed

    Ishiyama, Ken; Yamaguchi, Takuhiro; Eto, Tetsuya; Ohashi, Kazuteru; Uchida, Naoyuki; Kanamori, Heiwa; Fukuda, Takahiro; Miyamura, Koichi; Inoue, Yoshiko; Taguchi, Jun; Mori, Takehiko; Iwato, Koji; Morishima, Yasuo; Nagamura-Inoue, Tokiko; Atsuta, Yoshiko; Sakamaki, Hisashi; Takami, Akiyoshi

    2016-08-01

    Acute erythroid leukemia (FAB-M6) and acute megakaryoblastic leukemia (FAB-M7) exhibit closely related properties in cells regarding morphology and the gene expression profile. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is considered the mainstay of the treatment for both subtypes of leukemia due to their refractoriness to chemotherapy and high rates of relapse, it remains unclear whether allo-HSCT is curative in such cases due to their scarcity. We retrospectively examined the impact of allo-HSCT in 382 patients with M6 and 108 patients with M7 using nationwide HSCT data and found the overall survival (OS) and relapse rates of the M6 patients to be significantly better than those of the M7 patients after adjusting for confounding factors and statistically comparable with those of the patients with M0/M1/M2/M4/M5 disease. Consequently, the factors of age, gender, performance status, karyotype, disease status at HSCT and development of graft-vs.-host disease predicted the OS for the M6 patients, while the performance status and disease status at HSCT were predictive of the OS for the M7 patients. These findings substantiate the importance of distinguishing between M6 and M7 in the HSCT setting and suggest that unknown mechanisms influence the HSCT outcomes of these closely related subtypes of leukemia. PMID:27244257

  4. Iron as the Key Modulator of Hepcidin Expression in Erythroid Antibody-Mediated Hypoplasia

    PubMed Central

    Fernandes, J. C.; Garrido, P.; Ribeiro, S.; Rocha-Pereira, P.; Bronze-da-Rocha, E.; Belo, L.; Costa, E.; Reis, F.; Santos-Silva, A.

    2014-01-01

    Erythroid hypoplasia (EH) is a rare complication associated with recombinant human erythropoietin (rHuEPO) therapies, due to development of anti-rHuEPO antibodies; however, the underlying mechanisms remain poorly clarified. Our aim was to manage a rat model of antibody-mediated EH induced by rHuEPO and study the impact on iron metabolism and erythropoiesis. Wistar rats treated during 9 weeks with a high rHuEPO dose (200 IU) developed EH, as shown by anemia, reduced erythroblasts, reticulocytopenia, and plasmatic anti-rHuEPO antibodies. Serum iron was increased and associated with mRNA overexpression of hepatic hepcidin and other iron regulatory mediators and downregulation of matriptase-2; overexpression of divalent metal transporter 1 and ferroportin was observed in duodenum and liver. Decreased EPO expression was observed in kidney and liver, while EPO receptor was overexpressed in liver. Endogenous EPO levels were normal, suggesting that anti-rHuEPO antibodies blunted EPO function. Our results suggest that anti-rHuEPO antibodies inhibit erythropoiesis causing anemia. This leads to a serum iron increase, which seems to stimulate hepcidin expression despite no evidence of inflammation, thus suggesting iron as the key modulator of hepcidin synthesis. These findings might contribute to improving new therapeutic strategies against rHuEPO resistance and/or development of antibody-mediated EH in patients under rHuEPO therapy. PMID:25580431

  5. Measuring Energy Sustainability

    SciTech Connect

    Greene, David L

    2009-01-01

    For the purpose of measurement, energy sustainability is defined as ensuring that future generations have energy resources that enable them to achieve a level of well-being at least as good as that of the current generation. It is recognized that there are valid, more comprehensive understandings of sustainability and that energy sustainability as defined here is only meaningful when placed in a broader context. Still, measuring energy sustainability is important to society because the rates of consumption of some fossil resources are now substantial in relation to measures of ultimate resources, and because conflicts between fossil energy use and environmental sustainability are intensifying. Starting from the definition, an equation for energy sustainability is derived that reconciles renewable fl ows and nonrenewable stocks, includes the transformation of energy into energy services, incorporates technological change and, at least notionally, allows for changes in the relationship between energy services and societal well-being. Energy sustainability must be measured retrospectively as well as prospectively, and methods for doing each are discussed. Connections to the sustainability of other resources are also critical. The framework presented is merely a starting point; much remains to be done to make it operational.

  6. Sustainability Frontiers

    ERIC Educational Resources Information Center

    Selby, David

    2010-01-01

    This article introduces Sustainability Frontiers, a newly formed, international, not-for-profit alliance of sustainability and global educators dedicated to challenging and laying bare the assumptions, exposing the blind spots, and transgressing the boundaries of mainstream understandings of sustainability-related education. Among the orthodoxies…

  7. Control System for Sustainable Development

    NASA Astrophysics Data System (ADS)

    Carlman, Inga

    2008-10-01

    Ecological sustainability presupposes that a global human population acts in such ways, that their total impact on the biosphere, together with nature's reactions, keeps the biosphere sufficient for sustaining generations to come. Human conduct is ultimately controlled by means of law. The problem can be summed up as: Controlling system—Population—Sustainable ecosystems This paper discusses two interlinked issues: a) the social scientific need for systems theory in the context of achieving and maintaining sustainable development and b) how theory of anticipatory modelling and computing can be applied when constructing and applying societal controlling systems for ecological sustainability with as much local democracy and economic efficiency as possible.

  8. Sustainability Research Under EPA/NRMRL

    EPA Science Inventory

    Sustainability means different things to different people, but most can agree that maintaining and supporting critical ecosystems over the long term is important for environmental and human health. Achieving sustainability involves a broad view of environmental stewardship. When ...

  9. Achieving an intense enough maintenance electric field in a low-pressure discharge sustained by a microwave field under ambipolar diffusion regime such that periodic parametric instabilities are generated

    NASA Astrophysics Data System (ADS)

    Moisan, M.; Nowakowska, H.

    2015-11-01

    The intensity of the maintenance electric field of a given discharge is one of its internal parameters. Under ambipolar diffusion conditions, it is almost exclusively set by particle losses, which are related to the dimensions of the discharge vessel and to the gas pressure, and ultimately are determined by the electron energy distribution function. For instance, raising the density of microwave power absorbed in a discharge tube essentially increases the electron density without much increasing the amplitude of the maintenance E-field. To raise the intensity of this E-field in such a case, one needs to reduce the volume into which electromagnetic power is absorbed relative to the diffusion volume, i.e. the volume within which electrons transfer their power through collisions with heavy particles. To show this point, we consider a power balance based on the power lost per electron through collisions with heavy particles, θ L, to the power absorbed (over a period of the microwave field) per electron in the discharge, θ A. The power θ A, which depends on E02 , the square of the amplitude (intensity) of the maintenance electric field, adjusts to compensate for the power lost θ L. The analysis presented is achieved for a particular microwave discharge configuration that is known to provide an intense E 0-field, which means x  ⩾  λ De, where x is the oscillation amplitude of electrons in the E 0-field and λ De the electron Debye length. Such a condition allows one to observe periodic parametric instabilities at, or close to, the electron-plasma frequency f pe and at their corresponding ion-plasma frequency f pi, these oscillations being caused by the simultaneous propagation of an electron-plasma wave and an ion-plasma wave in the discharge as a result of an applied ‘pump’ power, which also sustains the discharge. A 2D hydrodynamic calculation of the specific plasma discharge system is performed, which yields the value of the x/λ De ratio in

  10. Expression of nuclear factor, erythroid 2-like 2-mediated genes differentiates tuberculosis.

    PubMed

    Qian, Zhongqing; Lv, Jingzhu; Kelly, Gabriel T; Wang, Hongtao; Zhang, Xiaojie; Gu, Wanjun; Yin, Xiaofeng; Wang, Ting; Zhou, Tong

    2016-07-01

    During infection and host defense, nuclear factor, erythroid 2-like 2 (Nrf2) dependent signaling is an efficient antioxidant defensive mechanism used by host cells to control the destructive effects of reactive oxygen species. This allows for effective defense responses against microbes while minimizing oxidative injury to the host cell itself. As a central regulator of antioxidant genes, Nrf2 has gained great attention in its pivotal role in infection, especially in tuberculosis (TB), the top infectious disease killer worldwide. To elucidate the genes potentially regulated by Nrf2 in TB, we conducted a meta-analysis on published gene expression datasets. Firstly, we compared the global gene expression profiles between control and Nrf2-deficient human cells. The differentially expressed genes were deemed as "Nrf2-mediated genes". Next, the whole blood gene expression pattern of TB patients was compared with that of healthy controls, pneumonia patients, and lung cancer patients. We found that the genes deregulated in TB significantly overlap with the Nrf2-mediated genes. Based on the intersection of Nrf2-mediated and TB-regulated genes, we identified an Nrf2-mediated 17-gene signature, which reflects a cluster of gene ontology terms highly related to TB physiology. We demonstrated that the 17-gene signature can be used to distinguish TB patients from healthy controls and patients with latent TB infection, pneumonia, or lung cancer. Also, the Nrf2-mediated gene signature can be used as an indicator of the anti-TB therapeutic response. More importantly, we confirmed that the predictive power of the Nrf2-mediated 17-gene signature is significantly better than the random gene sets selected from the human transcriptome. Also, the 17-gene signature performs even better than the random gene signatures selected from TB-associated genes. Our study confirms the central role of Nrf2 in TB pathogenesis and provides a novel and useful diagnostic method to differentiate TB

  11. Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection.

    PubMed

    Elahi, Shokrollah; Ertelt, James M; Kinder, Jeremy M; Jiang, Tony T; Zhang, Xuzhe; Xin, Lijun; Chaturvedi, Vandana; Strong, Beverly S; Qualls, Joseph E; Steinbrecher, Kris A; Kalfa, Theodosia A; Shaaban, Aimen F; Way, Sing Sing

    2013-12-01

    Newborn infants are highly susceptible to infection. This defect in host defence has generally been ascribed to the immaturity of neonatal immune cells; however, the degree of hyporesponsiveness is highly variable and depends on the stimulation conditions. These discordant responses illustrate the need for a more unified explanation for why immunity is compromised in neonates. Here we show that physiologically enriched CD71(+) erythroid cells in neonatal mice and human cord blood have distinctive immunosuppressive properties. The production of innate immune protective cytokines by adult cells is diminished after transfer to neonatal mice or after co-culture with neonatal splenocytes. Neonatal CD71(+) cells express the enzyme arginase-2, and arginase activity is essential for the immunosuppressive properties of these cells because molecular inhibition of this enzyme or supplementation with L-arginine overrides immunosuppression. In addition, the ablation of CD71(+) cells in neonatal mice, or the decline in number of these cells as postnatal development progresses parallels the loss of suppression, and restored resistance to the perinatal pathogens Listeria monocytogenes and Escherichia coli. However, CD71(+) cell-mediated susceptibility to infection is counterbalanced by CD71(+) cell-mediated protection against aberrant immune cell activation in the intestine, where colonization with commensal microorganisms occurs swiftly after parturition. Conversely, circumventing such colonization by using antimicrobials or gnotobiotic germ-free mice overrides these protective benefits. Thus, CD71(+) cells quench the excessive inflammation induced by abrupt colonization with commensal microorganisms after parturition. This finding challenges the idea that the susceptibility of neonates to infection reflects immune-cell-intrinsic defects and instead highlights processes that are developmentally more essential and inadvertently mitigate innate immune protection. We anticipate that

  12. Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection

    PubMed Central

    Elahi, Shokrollah; Ertelt, James M.; Kinder, Jeremy M.; Jiang, Tony T.; Zhang, Xuzhe; Xin, Lijun; Chaturvedi, Vandana; Strong, Beverly S.; Qualls, Joseph E.; Steinbrecher, Kris A.; Kalfa, Theodosia A.; Shaaban, Aimen F.; Way, Sing Sing

    2014-01-01

    Newborn infants are highly susceptible to infection. This defect in host defence has generally been ascribed to the immaturity of neonatal immune cells; however, the degree of hyporesponsiveness is highly variable and depends on the stimulation conditions1–7. These discordant responses illustrate the need for a more unified explanation for why immunity is compromised in neonates. Here we show that physiologically enriched CD71+ erythroid cells in neonatal mice and human cord blood have distinctive immunosuppressive properties. The production of innate immune protective cytokines by adult cells is diminished after transfer to neonatal mice or after co-culture with neonatal splenocytes. Neonatal CD71+ cells express the enzyme arginase-2, and arginase activity is essential for the immunosuppressive properties of these cells because molecular inhibition of this enzyme or supplementation with l-arginine overrides immunosuppression. In addition, the ablation of CD71+ cells in neonatal mice, or the decline in number of these cells as postnatal development progresses parallels the loss of suppression, and restored resistance to the perinatal pathogens Listeria monocytogenes and Escherichia coli8,9. However, CD71+ cell-mediated susceptibility to infection is counterbalanced by CD71+ cell-mediated protection against aberrant immune cell activation in the intestine, where colonization with commensal microorganisms occurs swiftly after parturition10,11.Conversely, circumventing such colonization by using antimicrobials or gnotobiotic germ-free mice overrides these protective benefits. Thus, CD71+ cells quench the excessive inflammation induced by abrupt colonization with commensal microorganisms after parturition. This finding challenges the idea that the susceptibility of neonates to infection reflects immune-cell-intrinsic defects and instead highlights processes that are developmentally more essential and inadvertently mitigate innate immune protection. We anticipate that

  13. Dynamic Transcription Factor Activity Profiles Reveal Key Regulatory Interactions During Megakaryocytic and Erythroid Differentiation

    PubMed Central

    Duncan, Mark T.; Shin, Seungjin; Wu, Jia J.; Mays, Zachary; Weng, Stanley; Bagheri, Neda; Miller, William M.; Shea, Lonnie D.

    2014-01-01

    The directed differentiation toward erythroid (E) or megakaryocytic (MK) lineages by the MK-E progenitor (MEP) could enhance the ex vivo generation of red blood cells and platelets for therapeutic transfusions. The lineage choice at the MEP bifurcation is controlled in large part by activity within the intracellular signal transduction network, the output of which determines the activity of transcription factors (TFs) and ultimately gene expression. Although many TFs have been implicated, E or MK differentiation is a complex process requiring multiple days, and the dynamics of TF activities during commitment and terminal maturation are relatively unexplored. Herein, we applied a living cell array for the large-scale, dynamic quantification of TF activities during MEP bifurcation. A panel of hematopoietic TFs (GATA-1, GATA-2, SCL/TAL1, FLI-1, NF-E2, PU.1, c-Myb) was characterized during E and MK differentiation of bipotent K562 cells. Dynamic TF activity profiles associated with differentiation towards each lineage were identified, and validated with previous reports. From these activity profiles, we show that GATA-1 is an important hub during early hemin- and PMA-induced differentiation, and reveal several characteristic TF interactions for E and MK differentiation that confirm regulatory mechanisms documented in the literature. Additionally, we highlight several novel TF interactions at various stages of E and MK differentiation. Furthermore, we investigated the mechanism by which nicotinamide (NIC) promoted terminal MK maturation using an MK-committed cell line, CHRF-288-11 (CHRF). Concomitant with its enhancement of ploidy, NIC strongly enhanced the activity of three TFs with known involvement in terminal MK maturation: FLI-1, NF-E2, and p53. Dynamic profiling of TF activity represents a novel tool to complement traditional assays focused on mRNA and protein expression levels to understand progenitor cell differentiation. PMID:24853077

  14. Dynamic transcription factor activity profiles reveal key regulatory interactions during megakaryocytic and erythroid differentiation.

    PubMed

    Duncan, Mark T; Shin, Seungjin; Wu, Jia J; Mays, Zachary; Weng, Stanley; Bagheri, Neda; Miller, William M; Shea, Lonnie D

    2014-10-01

    The directed differentiation toward erythroid (E) or megakaryocytic (MK) lineages by the MK-E progenitor (MEP) could enhance the ex vivo generation of red blood cells and platelets for therapeutic transfusions. The lineage choice at the MEP bifurcation is controlled in large part by activity within the intracellular signal transduction network, the output of which determines the activity of transcription factors (TFs) and ultimately gene expression. Although many TFs have been implicated, E or MK differentiation is a complex process requiring multiple days, and the dynamics of TF activities during commitment and terminal maturation are relatively unexplored. Herein, we applied a living cell array for the large-scale, dynamic quantification of TF activities during MEP bifurcation. A panel of hematopoietic TFs (GATA-1, GATA-2, SCL/TAL1, FLI-1, NF-E2, PU.1, c-Myb) was characterized during E and MK differentiation of bipotent K562 cells. Dynamic TF activity profiles associated with differentiation towards each lineage were identified, and validated with previous reports. From these activity profiles, we show that GATA-1 is an important hub during early hemin- and PMA-induced differentiation, and reveal several characteristic TF interactions for E and MK differentiation that confirm regulatory mechanisms documented in the literature. Additionally, we highlight several novel TF interactions at various stages of E and MK differentiation. Furthermore, we investigated the mechanism by which nicotinamide (NIC) promoted terminal MK maturation using an MK-committed cell line, CHRF-288-11 (CHRF). Concomitant with its enhancement of ploidy, NIC strongly enhanced the activity of three TFs with known involvement in terminal MK maturation: FLI-1, NF-E2, and p53. Dynamic profiling of TF activity represents a novel tool to complement traditional assays focused on mRNA and protein expression levels to understand progenitor cell differentiation. PMID:24853077

  15. Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection

    NASA Astrophysics Data System (ADS)

    Elahi, Shokrollah; Ertelt, James M.; Kinder, Jeremy M.; Jiang, Tony T.; Zhang, Xuzhe; Xin, Lijun; Chaturvedi, Vandana; Strong, Beverly S.; Qualls, Joseph E.; Steinbrecher, Kris A.; Kalfa, Theodosia A.; Shaaban, Aimen F.; Way, Sing Sing

    2013-12-01

    Newborn infants are highly susceptible to infection. This defect in host defence has generally been ascribed to the immaturity of neonatal immune cells; however, the degree of hyporesponsiveness is highly variable and depends on the stimulation conditions. These discordant responses illustrate the need for a more unified explanation for why immunity is compromised in neonates. Here we show that physiologically enriched CD71+ erythroid cells in neonatal mice and human cord blood have distinctive immunosuppressive properties. The production of innate immune protective cytokines by adult cells is diminished after transfer to neonatal mice or after co-culture with neonatal splenocytes. Neonatal CD71+ cells express the enzyme arginase-2, and arginase activity is essential for the immunosuppressive properties of these cells because molecular inhibition of this enzyme or supplementation with L-arginine overrides immunosuppression. In addition, the ablation of CD71+ cells in neonatal mice, or the decline in number of these cells as postnatal development progresses parallels the loss of suppression, and restored resistance to the perinatal pathogens Listeria monocytogenes and Escherichia coli. However, CD71+ cell-mediated susceptibility to infection is counterbalanced by CD71+ cell-mediated protection against aberrant immune cell activation in the intestine, where colonization with commensal microorganisms occurs swiftly after parturition. Conversely, circumventing such colonization by using antimicrobials or gnotobiotic germ-free mice overrides these protective benefits. Thus, CD71+ cells quench the excessive inflammation induced by abrupt colonization with commensal microorganisms after parturition. This finding challenges the idea that the susceptibility of neonates to infection reflects immune-cell-intrinsic defects and instead highlights processes that are developmentally more essential and inadvertently mitigate innate immune protection. We anticipate that these

  16. Recombinant erythroid differentiation regulator 1 inhibits both inflammation and angiogenesis in a mouse model of rosacea.

    PubMed

    Kim, Miri; Kim, Kyung-Eun; Jung, Haw Young; Jo, Hyunmu; Jeong, Seo-Won; Lee, Jahyung; Kim, Chang Han; Kim, Heejong; Cho, Daeho; Park, Hyun Jeong

    2015-09-01

    The erythroid differentiation regulator 1 (Erdr1), which is a novel and highly conserved factor, was recently reported to be negatively regulated by IL-18 and to play a crucial role as an antimetastatic factor. IL-18 is a proinflammatory cytokine that functions as an angiogenic mediator in inflammation. Rosacea is a chronic inflammatory skin disorder that is characterized by abnormal inflammation and vascular hyperactivity of the facial skin. To determine whether Erdr1 contributes to the regulation of the chronic inflammatory process in the development of rosacea, an immunohistochemical analysis was performed in healthy donors and patients with rosacea. In this study, we showed that Erdr1 was downregulated, whereas IL-18 was upregulated, in patients with rosacea, which led us to question the role of Erdr1 in this disorder. Moreover, a rosacea-like BALB/c mouse model was used to determine the role of Erdr1 in rosacea in vivo. LL-37 injection induced typical rosacea features, including erythema, telangiectasia and inflammation. Treatment with recombinant Erdr1 (rErdr1) resulted in a significant reduction of erythema, inflammatory cell infiltration (including CD4(+) and CD8(+) T cells), and microvessel density with vascular endothelial growth factor (VEGF). Taken together, our findings suggest that rErdr1 may be involved in attenuating the inflammation and angiogenesis associated with the pathogenesis of rosacea. Thus, these results provide new insight into the mechanism involved in this condition and indicate that rErdr1 could be a potential target for therapeutic intervention of rosacea. PMID:25940661

  17. Sustainability and Higher Education

    ERIC Educational Resources Information Center

    Hales, David

    2008-01-01

    People face four fundamental dilemmas, which are essentially moral choices: (1) alleviating poverty; (2) removing the gap between rich and poor; (3) controlling the use of violence for political ends; and (4) changing the patterns of production and consumption and achieving the transition to sustainability. The world in which future generations…

  18. Binding of polarity-sensitive hydrophobic ligands to erythroid and nonerythroid spectrin: fluorescence and molecular modeling studies.

    PubMed

    Patra, Malay; Mitra, Madhurima; Chakrabarti, Abhijit; Mukhopadhyay, Chaitali

    2014-01-01

    We have used three polarity-sensitive fluorescence probes, 6-propionyl 2-(N,N-dimethyl-amino) naphthalene (Prodan), pyrene and 8-anilino 1-naphthalene sulphonic acid, to study their binding with erythroid and nonerythroid spectrin, using fluorescence spectroscopy. We have found that both bind to prodan and pyrene with high affinities with apparent dissociation constants (Kd) of .50 and .17 μM, for prodan, and .04 and .02 μM, for pyrene, respectively. The most striking aspect of these bindings have been that the binding stoichiometry have been equal to 1 in erythroid spectrin, both in dimeric and tetrameric form, and in tetrameric nonerythroid spectrin. From an estimate of apparent dielectric constants, the polarity of the binding site in both erythroid and nonerythroid forms have been found to be extremely hydrophobic. Thermodynamic parameters associated with such binding revealed that the binding is favored by positive change in entropy. Molecular docking studies alone indicate that both prodan and pyrene bind to the four major structural domains, following the order in the strength of binding to the Ankyrin binding domain > SH3 domain > Self-association domain > N-terminal domain of α-spectrin of both forms of spectrin. The binding experiments, particularly with the tetrameric nonerythroid spectrin, however, indicate more toward the self association domain in offering the unique binding site, since the binding stoichiometry have been 1 in all forms of dimeric and tetrameric spectrin, so far studied by us. Further studies are needed to characterize the hydrophobic binding sites in both forms of spectrin. PMID:24404769

  19. Embryonic----Fetal Hb switch in humans: studies on erythroid bursts generated by embryonic progenitors from yolk sac and liver.

    PubMed

    Peschle, C; Migliaccio, A R; Migliaccio, G; Petrini, M; Calandrini, M; Russo, G; Mastroberardino, G; Presta, M; Gianni, A M; Comi, P

    1984-04-01

    The synthesis of embryonic (zeta, epsilon), fetal (alpha, gamma), and adult (beta) globin was evaluated in human yolk sacs (YS) and livers at different ontogenic stages (i.e., from 6 through 10-12 wk of age) by means of analytical isoelectric focusing. Globin production was comparatively evaluated in vivo (i.e., in directly labeled erythroblasts from YS and liver) and in vitro [i.e., in erythroid bursts generated in culture by erythroid burst-forming units (BFU-E) from the same erythropoietic tissues]. Erythroid bursts generated in vitro by BFU-E from 6-wk livers and YS show essentially a "fetal" globin synthetic pattern: this is in sharp contrast to the "embryonic" pattern in corresponding liver and YS erythroblasts directly labeled in vivo. The invitro phenomenon suggests that (i) 6-wk BFU-E constitute a new generation of progenitors, which have already switched from an embryonic to a fetal program, and/or (ii) expression of their fetal program is induced by unknown in vitro factor(s), which may underlie the in vivo switch at later ontogenic stages. It is emphasized that 6- to 7-wk BFU-E are endowed with the potential for in vitro synthesis of not only epsilon- and gamma-chains but also some beta-globin. In general, we observed an inverse correlation between the levels of epsilon- and beta-chain synthesis. These results, together with previous studies on fetal, perinatal, and adult BFU-E, are compatible with models suggesting that in ontogeny the chromatin configuration is gradually modified at the level of the non-alpha gene cluster, thus leading to a 5'----3' activation of globin genes in a balanced fashion. PMID:6201856

  20. Hematopoietic deletion of transferrin receptor 2 in mice leads to a block in erythroid differentiation during iron-deficient anemia.

    PubMed

    Rishi, Gautam; Secondes, Eriza S; Wallace, Daniel F; Subramaniam, V Nathan

    2016-08-01

    Iron metabolism and erythropoiesis are inherently interlinked physiological processes. Regulation of iron metabolism is mediated by the iron-regulatory hormone hepcidin. Hepcidin limits the amount of iron released into the blood by binding to and causing the internalization of the iron exporter, ferroportin. A number of molecules and physiological stimuli, including erythropoiesis, are known to regulate hepcidin. An increase in erythropoietic demand decreases hepcidin, resulting in increased bioavailable iron in the blood. Transferrin receptor 2 (TFR2) is involved in the systemic regulation of iron metabolism. Patients and mice with mutations in TFR2 develop hemochromatosis due to inappropriate hepcidin levels relative to body iron. Recent studies from our laboratory and others have suggested an additional role for TFR2 in response to iron-restricted erythropoiesis. These studies used mouse models with perturbed systemic iron metabolism: anemic mice lacking matriptase-2 and Tfr2, or bone marrow transplants from iron-loaded Tfr2 null mice. We developed a novel transgenic mouse model which lacks Tfr2 in the hematopoietic compartment, enabling the delineation of the role of Tfr2 in erythroid development without interfering with its role in systemic iron metabolism. We show that in the absence of hematopoietic Tfr2 immature polychromatic erythroblasts accumulate with a concordant reduction in the percentage of mature erythroid cells in the spleen and bone marrow of anemic mice. These results demonstrate that erythroid Tfr2 is essential for an appropriate erythropoietic response in iron-deficient anemia. These findings may be of relevance in clinical situations in which an immediate and efficient erythropoietic response is required. Am. J. Hematol. 91:812-818, 2016. © 2016 Wiley Periodicals, Inc. PMID:27169626

  1. Sustainability 101

    ERIC Educational Resources Information Center

    Shi, David

    2008-01-01

    Sustainability is one of the leading issues of this time. Climate change is real, and widespread commitment and creativity are needed to combat its negative effects. Higher education is the seedbed of the sustainability movement. Much climate research and environmental science takes place on college and university campuses, which are, by their…

  2. Sustainable Learning

    ERIC Educational Resources Information Center

    Cadwell, Louise; Dillon, Robert

    2011-01-01

    Green schools have moved into a new era that focuses on building a culture of sustainability in every aspect of learning in schools. In the early stages of sustainability education, the focus was on recycling and turning off the lights. Now, students and adults together are moving into the areas of advocacy and action that are based on a deep…

  3. Sustainable Biofuels Development Center

    SciTech Connect

    Reardon, Kenneth F.

    2015-03-01

    The mission of the Sustainable Bioenergy Development Center (SBDC) is to enhance the capability of America’s bioenergy industry to produce transportation fuels and chemical feedstocks on a large scale, with significant energy yields, at competitive cost, through sustainable production techniques. Research within the SBDC is organized in five areas: (1) Development of Sustainable Crops and Agricultural Strategies, (2) Improvement of Biomass Processing Technologies, (3) Biofuel Characterization and Engine Adaptation, (4) Production of Byproducts for Sustainable Biorefining, and (5) Sustainability Assessment, including evaluation of the ecosystem/climate change implication of center research and evaluation of the policy implications of widespread production and utilization of bioenergy. The overall goal of this project is to develop new sustainable bioenergy-related technologies. To achieve that goal, three specific activities were supported with DOE funds: bioenergy-related research initiation projects, bioenergy research and education via support of undergraduate and graduate students, and Research Support Activities (equipment purchases, travel to attend bioenergy conferences, and seminars). Numerous research findings in diverse fields related to bioenergy were produced from these activities and are summarized in this report.

  4. Sustainability Base Construction Update

    NASA Technical Reports Server (NTRS)

    Mewhinney, Michael

    2012-01-01

    Construction of the new Sustainability Base Collaborative support facility, expected to become the highest performing building in the federal government continues at NASA's Ames Research Center, Moffet Field, Calif. The new building is designed to achieve a platinum rating under the leadership in Energy and Environment Design (LEED) new construction standards for environmentally sustainable construction developed by the U. S. Green Building Council, Washington, D. C. When completed by the end of 2011, the $20.6 million building will feature near zero net energy consumption, use 90 percent less potable water than conventionally build buildings of equivalent size, and will result in reduced building maintenance costs.

  5. UFBP1, a Key Component of the Ufm1 Conjugation System, Is Essential for Ufmylation-Mediated Regulation of Erythroid Development.

    PubMed

    Cai, Yafei; Pi, Wenhu; Sivaprakasam, Satish; Zhu, Xiaobin; Zhang, Mingsheng; Chen, Jijun; Makala, Levi; Lu, Chunwan; Wu, Jianchu; Teng, Yong; Pace, Betty; Tuan, Dorothy; Singh, Nagendra; Li, Honglin

    2015-11-01

    The Ufm1 conjugation system is an ubiquitin-like modification system that consists of Ufm1, Uba5 (E1), Ufc1 (E2), and less defined E3 ligase(s) and targets. The biological importance of this system is highlighted by its essential role in embryogenesis and erythroid development, but the underlying mechanism is poorly understood. UFBP1 (Ufm1 binding protein 1, also known as DDRGK1, Dashurin and C20orf116) is a putative Ufm1 target, yet its exact physiological function and impact of its ufmylation remain largely undefined. In this study, we report that UFBP1 is indispensable for embryonic development and hematopoiesis. While germ-line deletion of UFBP1 caused defective erythroid development and embryonic lethality, somatic ablation of UFBP1 impaired adult hematopoiesis, resulting in pancytopenia and animal death. At the cellular level, UFBP1 deficiency led to elevated ER (endoplasmic reticulum) stress and activation of unfolded protein response (UPR), and consequently cell death of hematopoietic stem/progenitor cells. In addition, loss of UFBP1 suppressed expression of erythroid transcription factors GATA-1 and KLF1 and blocked erythroid differentiation from CFU-Es (colony forming unit-erythroid) to proerythroblasts. Interestingly, depletion of Uba5, a Ufm1 E1 enzyme, also caused elevation of ER stress and under-expression of erythroid transcription factors in erythroleukemia K562 cells. By contrast, knockdown of ASC1, a newly identified Ufm1 target that functions as a transcriptional co-activator of hormone receptors, led to down-regulation of erythroid transcription factors, but did not elevate basal ER stress. Furthermore, we found that ASC1 was associated with the promoters of GATA-1 and Klf1 in a UFBP1-dependent manner. Taken together, our findings suggest that UFBP1, along with ASC1 and other ufmylation components, play pleiotropic roles in regulation of hematopoietic cell survival and differentiation via modulating ER homeostasis and erythroid lineage

  6. UFBP1, a Key Component of the Ufm1 Conjugation System, Is Essential for Ufmylation-Mediated Regulation of Erythroid Development

    PubMed Central

    Cai, Yafei; Pi, Wenhu; Sivaprakasam, Satish; Zhu, Xiaobin; Zhang, Mingsheng; Chen, Jijun; Makala, Levi; Lu, Chunwan; Wu, Jianchu; Teng, Yong; Pace, Betty; Tuan, Dorothy; Singh, Nagendra; Li, Honglin

    2015-01-01

    The Ufm1 conjugation system is an ubiquitin-like modification system that consists of Ufm1, Uba5 (E1), Ufc1 (E2), and less defined E3 ligase(s) and targets. The biological importance of this system is highlighted by its essential role in embryogenesis and erythroid development, but the underlying mechanism is poorly understood. UFBP1 (Ufm1 binding protein 1, also known as DDRGK1, Dashurin and C20orf116) is a putative Ufm1 target, yet its exact physiological function and impact of its ufmylation remain largely undefined. In this study, we report that UFBP1 is indispensable for embryonic development and hematopoiesis. While germ-line deletion of UFBP1 caused defective erythroid development and embryonic lethality, somatic ablation of UFBP1 impaired adult hematopoiesis, resulting in pancytopenia and animal death. At the cellular level, UFBP1 deficiency led to elevated ER (endoplasmic reticulum) stress and activation of unfolded protein response (UPR), and consequently cell death of hematopoietic stem/progenitor cells. In addition, loss of UFBP1 suppressed expression of erythroid transcription factors GATA-1 and KLF1 and blocked erythroid differentiation from CFU-Es (colony forming unit-erythroid) to proerythroblasts. Interestingly, depletion of Uba5, a Ufm1 E1 enzyme, also caused elevation of ER stress and under-expression of erythroid transcription factors in erythroleukemia K562 cells. By contrast, knockdown of ASC1, a newly identified Ufm1 target that functions as a transcriptional co-activator of hormone receptors, led to down-regulation of erythroid transcription factors, but did not elevate basal ER stress. Furthermore, we found that ASC1 was associated with the promoters of GATA-1 and Klf1 in a UFBP1-dependent manner. Taken together, our findings suggest that UFBP1, along with ASC1 and other ufmylation components, play pleiotropic roles in regulation of hematopoietic cell survival and differentiation via modulating ER homeostasis and erythroid lineage

  7. [Peculiarities of antioxidant defense system in erythroid cells and tissues of pigs under action of chromium chloride].

    PubMed

    Iskra, R Ia; Vlizlo, V V

    2013-01-01

    The influence of CrCI3 in the amount of 400 mg Cr/kg of feed on antioxidant defense in populations of erythrocytes, erythroid bone marrow cells and tissues of pigs was studied. The increasing of the antioxidant defense of swine organism, as evidenced by the increase in superoxide dismutase and glutathione peroxidase activity in the fractions of "young" erythrocytes, was shown. Superoxide dismutase activity decreases, while glutathione and catalase activity increases in the erythroid cells of the bone marrow after of CrCl3 action. Oxidative processes are intensified in the liver of pigs of the experimental group, in contrast to other tissues, leading to the increase of content of TBARS-products, growth of superoxide dismutase activity and reduction of glutathione peroxidase activity. At the same time, the action of CrCl3 in other tissues activates antioxidant system, including the kidneys, lungs and myocardium, increases superoxide dismutase activity, and catalase activity in the spleen and kidneys. A decrease of content of TBARS-products and reduction of superoxide dismutase activity, as well as the increase of katalase activity and reduction of glutathione content were discovered in the skeletal muscles of pigs of the experimental group. As a result of research it is suggested to add CrCl3 to the diet of pigs to enhance antioxidant defense during their intensive growth. PMID:23940874

  8. Immunophenotypic Profiling of Erythroid Progenitor-Derived Extracellular Vesicles in Diamond-Blackfan Anaemia: A New Diagnostic Strategy

    PubMed Central

    Macrì, Serena; Aspesi, Anna; Vizziello, Claudia; Botto, Carlotta; Corti, Paola; Quarello, Paola; Notari, Patrizia; Ramenghi, Ugo; Ellis, Steven Robert; Dianzani, Irma

    2015-01-01

    Diamond-Blackfan Anaemia (DBA) is a rare inherited anaemia caused by heterozygous mutations in one of 13 ribosomal protein genes. Erythroid progenitors (BFU-E and CFU-E) in bone marrow (BM) show a proapoptotic phenotype. Suspicion of DBA is reached after exclusion of other forms of BM failure syndromes. To improve DBA diagnosis, which is confirmed by mutation analysis, we tested a new approach based on the study of extracellular vesicles (EVs) isolated from plasma by differential centrifugations and analysed by flow cytometry. We chose CD34, CD71 and CD235a markers to study erythroid EVs. We characterised the EVs immunophentoypic profiles of 13 DBA patients, 22 healthy controls and 16 patients with other haematological diseases. Among the three EVs clusters we found, only the CD34+/CD71low population showed statistically significant differences between DBA patients and controls (p< 0.05). The absence of this cluster is in agreement with the low levels of BFU-E found in DBA patients. The assessment of ROC curves demonstrated the potential diagnostic value of this population. We suggest that this assay may be useful to improve DBA diagnosis as a quicker and less invasive alternative to BM BFU-E culture analysis. PMID:26394034

  9. Evolving insights into the synergy between erythropoietin and thrombopoietin and the bipotent erythroid/megakaryocytic progenitor cell.

    PubMed

    Papayannopoulou, Thalia; Kaushansky, Kenneth

    2016-08-01

    Although the synergy between erythropoietin and thrombopoietin has previously been pointed out, the clonal demonstration of a human bipotent erythroid/megakaryocytic progenitor (MEP) was first published in Experimental Hematology (Papayannopoulou T, Brice M, Farrer D, Kaushansky K. Exp Hematol. 1996;24:660-669) and later in the same year in Blood (Debili N, Coulombel L, Croisille L, et al. Blood. 1996;88:1284-1296). This demonstration, and the fact that both bipotent and monopotent erythroid or megakaryocytic progenitors co-express markers of both lineages and respond to both lineage-specific transcription factors, has provided a background for the extensive use of MEP assessment by fluorescence-activated cell sorting in many subsequent studies. Beyond this, the demonstration of shared regulatory elements and the presence of single mutations affecting both lineages have inspired further studies to decipher how the shift in transcription factor networks occurs from one lineage to the other. Furthermore, in addition to shared effects, erythropoietin and thrombopoietin have additional independent effects. Most notable for thrombopoietin is its effect on hematopoietic stem cells illustrated by in vitro and in vivo approaches. PMID:26773569

  10. Immunophenotypic Profiling of Erythroid Progenitor-Derived Extracellular Vesicles in Diamond-Blackfan Anaemia: A New Diagnostic Strategy.

    PubMed

    Macrì, Serena; Pavesi, Elisa; Crescitelli, Rossella; Aspesi, Anna; Vizziello, Claudia; Botto, Carlotta; Corti, Paola; Quarello, Paola; Notari, Patrizia; Ramenghi, Ugo; Ellis, Steven Robert; Dianzani, Irma

    2015-01-01

    Diamond-Blackfan Anaemia (DBA) is a rare inherited anaemia caused by heterozygous mutations in one of 13 ribosomal protein genes. Erythroid progenitors (BFU-E and CFU-E) in bone marrow (BM) show a proapoptotic phenotype. Suspicion of DBA is reached after exclusion of other forms of BM failure syndromes. To improve DBA diagnosis, which is confirmed by mutation analysis, we tested a new approach based on the study of extracellular vesicles (EVs) isolated from plasma by differential centrifugations and analysed by flow cytometry. We chose CD34, CD71 and CD235a markers to study erythroid EVs. We characterised the EVs immunophentoypic profiles of 13 DBA patients, 22 healthy controls and 16 patients with other haematological diseases. Among the three EVs clusters we found, only the CD34+/CD71low population showed statistically significant differences between DBA patients and controls (p< 0.05). The absence of this cluster is in agreement with the low levels of BFU-E found in DBA patients. The assessment of ROC curves demonstrated the potential diagnostic value of this population. We suggest that this assay may be useful to improve DBA diagnosis as a quicker and less invasive alternative to BM BFU-E culture analysis. PMID:26394034

  11. Erythroid Krüppel-like factor (EKLF) contains a multifunctional transcriptional activation domain important for inter- and intramolecular interactions.

    PubMed Central

    Chen, X; Bieker, J J

    1996-01-01

    Erythroid Krüppel-like factor (EKLF) is a red cell-restricted transcriptional activator that plays a dominant role in establishing high levels of beta-globin gene expression during erythroid ontogeny. Although its DNA binding domain belongs to the well-studied class of Krüppel-like zinc fingers, its proline-rich activation region has not been thoroughly examined. We have analyzed this region by monitoring the functional effects of its mutagenesis upon EKLF activity in vivo and in vitro. First, using co-transfection assays, we find that the transactivation region contains discrete stimulatory and inhibitory subdomains. Second, in vitro binding assays indicate that the inhibitory domain exerts its effect in cis by interfering with DNA binding. Third, in vivo competition assays demonstrate that EKLF interacts with a positive-acting cellular factor, and that the domain responsible for this trans interaction lies within a 40 amino acid sequence that is coincident with the EKLF minimal transactivation domain. Finally, site-directed mutagenesis of this domain implies that conformation and/or phosphorylation status of its central core may be critical for such interactions. These results point towards post-translational steric and/or allosteric control of EKLF function that may be important not just for its DNA binding ability, but also for its potential to interact with other proteins that fully establish the correct stereospecific array leading to efficient switching of beta-globin transcription during development. Images PMID:8918466

  12. Role of the mitochondrial amino acid pool in the differential sensitivity of erythroid and myeloid cells to chloramphenicol

    SciTech Connect

    Abou-Khalil, S.; Abou-Khalil, W.H.; Whitney, P.L.; Yunis, A.A.

    1986-05-01

    Previous studies in the authors laboratory have suggested that mitochondrial amino acid (AA) pool is involved in the differential sensitivity of erythroid and myeloid cells to chloramphenicol (CAP). The present study examines the role of AA pool by analysis of its composition and testing the effects of its major components. The endogenous AA composition of isolated mitochondria protein was determined using a JEOL 5AH AA analyzer. L-(/sup 14/C) leucine incorporation into mitochondrial protein was used to measure the rate of protein synthesis. Analysis of the endogenous pool in erythroleukemia (EM) and chloroleukemia (CM) mitochrondria showed similar total amount of AAs. However, some AAs were present in significantly higher or lower quantity within EM and CM (i.e. EM had about 2-fold higher glycine content). When compensating for each low AA addition of that particular acid to the reaction medium, only glycine and serine had significant effect. Thus, the addition of increasing concentrations of glycine or serine enhanced the sensitivity to CAP from 14% to 49-51% in CM but not in EM. Other AAs gave little or no effect. Since glycine is one of the first reactants in heme biosynthesis within mitochondria and is interconvertible with serine, it would appear that erythroid cells sensitivity to CAP is determined by the mitochondrial glycine-serine pool and may be somehow related of the pathway to heme biosynthesis in these cells.

  13. LRF is an essential downstream target of GATA1 in erythroid development and regulates BIM-dependent apoptosis.

    PubMed

    Maeda, Takahiro; Ito, Keisuke; Merghoub, Taha; Poliseno, Laura; Hobbs, Robin M; Wang, Guocan; Dong, Lin; Maeda, Manami; Dore, Louis C; Zelent, Arthur; Luzzatto, Lucio; Teruya-Feldstein, Julie; Weiss, Mitchell J; Pandolfi, Pier Paolo

    2009-10-01

    GATA-1-dependent transcription is essential for erythroid differentiation and maturation. Suppression of programmed cell death is also thought to be critical for this process; however, the link between these two features of erythropoiesis has remained elusive. Here, we show that the POZ-Krüppel family transcription factor, LRF (also known as Zbtb7a/Pokemon), is a direct target of GATA1 and plays an essential antiapoptotic role during terminal erythroid differentiation. We find that loss of Lrf leads to lethal anemia in embryos, due to increased apoptosis of late-stage erythroblasts. This programmed cell death is Arf and p53 independent and is instead mediated by upregulation of the proapoptotic factor Bim. We identify Lrf as a direct repressor of Bim transcription. In strong support of this mechanism, genetic Bim loss delays the lethality of Lrf-deficient embryos and rescues their anemia phenotype. Thus, our data define a key transcriptional cascade for effective erythropoiesis, whereby GATA-1 suppresses BIM-mediated apoptosis via LRF. PMID:19853566

  14. LRF is an essential downstream target of GATA1 in erythroid development and regulates BIM-dependent apoptosis

    PubMed Central

    Maeda, Takahiro; Ito, Keisuke; Merghoub, Taha; Poliseno, Laura; Hobbs, Robin M.; Wang, Guocan; Dong, Lin; Maeda, Manami; Dore, Louis C.; Zelent, Arthur; Luzzatto, Lucio; Teruya-Feldstein, Julie; Weiss, Mitchell J.; Pandolfi, Pier Paolo

    2011-01-01

    SUMMARY GATA-1-dependent transcription is essential for erythroid differentiation and maturation. Suppression of programmed cell death is also thought to be critical for this process; however, the link between these two features of erythropoiesis has remained elusive. Here, we show that the POZ-Krüppel family transcription factor, LRF (also known as Zbtb7a/Pokemon), is a direct target of GATA1 and plays an essential anti-apoptotic role during terminal erythroid differentiation. We find that loss of Lrf leads to lethal anemia in embryos, due to increased apoptosis of late stage erythroblasts. This programmed cell death is Arf- and p53-independent and is instead mediated by up-regulation of the pro-apoptotic factor Bim. We identify Lrf as a direct repressor of Bim transcription. In strong support of this mechanism, genetic Bim-loss delays the lethality of Lrf-deficient embryos and rescues their anemia-phenotype. Thus, our data defines a key transcriptional cascade for effective erythropoiesis, whereby GATA-1 suppresses BIM-mediated apoptosis via LRF. PMID:19853566

  15. Structural and functional characterization of an atypical activation domain in erythroid Krüppel-like factor (EKLF)

    PubMed Central

    Mas, Caroline; Lussier-Price, Mathieu; Soni, Shefali; Morse, Thomas; Arseneault, Geneviève; Di Lello, Paola; Lafrance-Vanasse, Julien; Bieker, James J.; Omichinski, James G.

    2011-01-01

    Erythroid Krüppel-like factor (EKLF) plays an important role in erythroid development by stimulating β-globin gene expression. We have examined the details by which the minimal transactivation domain (TAD) of EKLF (EKLFTAD) interacts with several transcriptional regulatory factors. We report that EKLFTAD displays homology to the p53TAD and, like the p53TAD, can be divided into two functional subdomains (EKLFTAD1 and EKLFTAD2). Based on sequence analysis, we found that EKLFTAD2 is conserved in KLF2, KLF4, KLF5, and KLF15. In addition, we demonstrate that EKLFTAD2 binds the amino-terminal PH domain of the Tfb1/p62 subunit of TFIIH (Tfb1PH/p62PH) and four domains of CREB-binding protein/p300. The solution structure of the EKLFTAD2/Tfb1PH complex indicates that EKLFTAD2 binds Tfb1PH in an extended conformation, which is in contrast to the α-helical conformation seen for p53TAD2 in complex with Tfb1PH. These studies provide detailed mechanistic information into EKLFTAD functions as well as insights into potential interactions of the TADs of other KLF proteins. In addition, they suggest that not only have acidic TADs evolved so that they bind using different conformations on a common target, but that transitioning from a disordered to a more ordered state is not a requirement for their ability to bind multiple partners. PMID:21670263

  16. Identification of a novel agrin-dependent pathway in cell signaling and adhesion within the erythroid niche

    PubMed Central

    Anselmo, A; Lauranzano, E; Soldani, C; Ploia, C; Angioni, R; D'amico, G; Sarukhan, A; Mazzon, C; Viola, A

    2016-01-01

    Establishment of cell–cell adhesion is crucial in embryonic development as well as within the stem cell niches of an adult. Adhesion between macrophages and erythroblasts is required for the formation of erythroblastic islands, specialized niches where erythroblasts proliferate and differentiate to produce red blood cells throughout life. The Eph family is the largest known family of receptor tyrosine kinases (RTKs) and controls cell adhesion, migration, invasion and morphology by modulating integrin and adhesion molecule activity and by modifying the actin cytoskeleton. Here, we identify the proteoglycan agrin as a novel regulator of Eph receptor signaling and characterize a novel mechanism controlling cell–cell adhesion and red cell development within the erythroid niche. We demonstrate that agrin induces clustering and activation of EphB1 receptors on developing erythroblasts, leading to the activation of α5β1 integrins. In agreement, agrin knockout mice display severe anemia owing to defective adhesion to macrophages and impaired maturation of erythroid cells. These results position agrin-EphB1 as a novel key signaling couple regulating cell adhesion and erythropoiesis. PMID:26990660

  17. Induction of gamma-globin gene transcription by hydroxycarbamide in primary erythroid cell cultures from Lepore patients.

    PubMed

    Calzolari, Roberta; Pecoraro, Alice; Borruso, Vito; Troia, Antonio; Acuto, Santina; Maggio, Aurelio; Di Marzo, Rosalba

    2008-05-01

    Increased expression of fetal haemoglobin (HbF) may ameliorate the clinical course of beta-thalassemia and sickle cell disease. Some pharmacological agents, such as hydroxycarbamide (HC), can increase fetal haemoglobin synthesis during adult life. Cellular selection and/or molecular mechanisms have been proposed to account for this increase. To explore the mechanism of action of HC we focused on homozygous Hb-Lepore patients that presented with high fetal haemoglobin levels and were good responders to HC treatment "in vivo". We performed primary erythroid cultures from peripheral blood of four homozygous Lepore patients. The increase in HBG (gamma-globin) transcription levels and HbF content in these cultures, after HC treatment, were detected by quantitative real time polymerase chain reaction analysis and flow cytometric analysis. Primary transcript "in-situ" hybridization analysis showed a 2-fold increase in the number of cells expressing both HBG alleles in HC-treated erythroid cultures. These studies, demonstrating the larger number of biallelic HBG expressing cells, suggest that HC is able to stimulate the activation of HBG transcription. These observations provide evidences that the molecular mechanism of action is involved in the increase of fetal haemoglobin production by HC. PMID:18422777

  18. Haem is necessary for a continued increase in ferrochelatase mRNA in murine erythroleukaemia cells during erythroid differentiation.

    PubMed

    Fukuda, Y; Fujita, H; Taketani, S; Sassa, S

    1993-12-01

    The level of mRNA encoding ferrochelatase (FeC) was examined in two murine erythroleukaemia (MEL) clones, DS and DR, a DMSO-sensitive, and a DMSO-resistant clone, respectively. DS cells undergo erythroid differentiation by DMSO treatment with a marked increase in haem synthesis, while DR cells fail to do so due to the lack of the erythroid-specific delta-aminolaevulinate synthase (ALAS-E). Both DS and DR cells showed an increase in the level of FeC mRNA within 18 h of DMSO treatment. The level of FeC mRNA in DR cells was then decreased, while that in DS cells continued to increase for 72 h. Treatment with haemin significantly increased FeC mRNA in DR cells. When cells were treated with both DMSO and haemin, the level of FeC mRNA in DR cells increased to a level comparable to that in DS cells. These findings suggest that the failure to maintain increased FeC mRNA DR cells after DMSO treatment may be due to a deficiency of haem in these cells. PMID:7918029

  19. Identification of a novel agrin-dependent pathway in cell signaling and adhesion within the erythroid niche.

    PubMed

    Anselmo, A; Lauranzano, E; Soldani, C; Ploia, C; Angioni, R; D'amico, G; Sarukhan, A; Mazzon, C; Viola, A

    2016-08-01

    Establishment of cell-cell adhesion is crucial in embryonic development as well as within the stem cell niches of an adult. Adhesion between macrophages and erythroblasts is required for the formation of erythroblastic islands, specialized niches where erythroblasts proliferate and differentiate to produce red blood cells throughout life. The Eph family is the largest known family of receptor tyrosine kinases (RTKs) and controls cell adhesion, migration, invasion and morphology by modulating integrin and adhesion molecule activity and by modifying the actin cytoskeleton. Here, we identify the proteoglycan agrin as a novel regulator of Eph receptor signaling and characterize a novel mechanism controlling cell-cell adhesion and red cell development within the erythroid niche. We demonstrate that agrin induces clustering and activation of EphB1 receptors on developing erythroblasts, leading to the activation of α5β1 integrins. In agreement, agrin knockout mice display severe anemia owing to defective adhesion to macrophages and impaired maturation of erythroid cells. These results position agrin-EphB1 as a novel key signaling couple regulating cell adhesion and erythropoiesis. PMID:26990660

  20. Sustainable Development.

    ERIC Educational Resources Information Center

    Auerbach, Raymond

    1994-01-01

    Discusses South African national development priorities, sustainable development, and the future of agriculture and presents three scenarios of possible national action: production for sale and export, household food security, and conservation of natural resources. (MKR)

  1. Sustainable markets for sustainable energy

    SciTech Connect

    Millan, J.; Smyser, C.

    1997-12-01

    The author discusses how the Inter-American Development Bank (IDB) is involved in sustainable energy development. It presently has 50 loans and grants for non conventional renewable energy projects and ten grants for efficiency programs for $600 and $17 million respectively, representing 100 MW of power. The IDB is concerned with how to create a sustainable market for sustainable energy projects. The IDB is trying to work with government, private sector, NGOs, trading allies, credit sources, and regulators to find proper roles for such projects. He discusses how the IDB is working to expand its vision and objectives in renewable energy projects in Central and South America.

  2. Erythroid activator NF-E2, TAL1 and KLF1 play roles in forming the LCR HSs in the human adult β-globin locus.

    PubMed

    Kim, Yea Woon; Yun, Won Ju; Kim, AeRi

    2016-06-01

    The β-like globin genes are developmental stage specifically transcribed in erythroid cells. The transcription of the β-like globin genes requires erythroid specific activators such as GATA-1, NF-E2, TAL1 and KLF1. However, the roles of these activators have not fully elucidated in transcription of the human adult β-globin gene. Here we employed hybrid MEL cells (MEL/ch11) where a human chromosome containing the β-globin locus is present and the adult β-globin gene is highly transcribed by induction. The roles of erythroid specific activators were analyzed by inhibiting the expression of NF-E2, TAL1 or KLF1 in MEL/ch11 cells. The loss of each activator decreased the transcription of human β-globin gene, locus wide histone hyperacetylation and the binding of other erythroid specific activators including GATA-1, even though not affecting the expression of other activators. Notably, sensitivity to DNase I was reduced in the locus control region (LCR) hypersensitive sites (HSs) with the depletion of activators. These results indicate that NF-E2, TAL1 and KLF1, all activators play a primary role in HSs formation in the LCR. It might contribute to the transcription of human adult β-globin gene by allowing the access of activators and cofactors. The roles of activators in the adult β-globin locus appear to be different from the roles in the early fetal locus. PMID:27026582

  3. Global transcriptome and chromatin occupancy analysis reveal the short isoform of GATA1 is deficient for erythroid specification and gene expression

    PubMed Central

    Chlon, Timothy M.; McNulty, Maureen; Goldenson, Benjamin; Rosinski, Alexander; Crispino, John D.

    2015-01-01

    GATA1 is a master transcriptional regulator of the differentiation of several related myeloid blood cell types, including erythrocytes and megakaryocytes. Germ-line mutations that cause loss of full length GATA1, but allow for expression of the short isoform (GATA1s), are associated with defective erythropoiesis in a subset of patients with Diamond Blackfan Anemia. Despite extensive studies of GATA1s in megakaryopoiesis, the mechanism by which GATA1s fails to support normal erythropoiesis is not understood. In this study, we used global gene expression and chromatin occupancy analysis to compare the transcriptional activity of GATA1s to GATA1. We discovered that compared to GATA1, GATA1s is less able to activate the erythroid gene expression program and terminal differentiation in cells with dual erythroid-megakaryocytic differentiation potential. Moreover, we found that GATA1s bound to many of its erythroid-specific target genes less efficiently than full length GATA1. These results suggest that the impaired ability of GATA1s to promote erythropoiesis in DBA may be caused by failure to occupy erythroid-specific gene regulatory elements. PMID:25682601

  4. Global transcriptome and chromatin occupancy analysis reveal the short isoform of GATA1 is deficient for erythroid specification and gene expression.

    PubMed

    Chlon, Timothy M; McNulty, Maureen; Goldenson, Benjamin; Rosinski, Alexander; Crispino, John D

    2015-05-01

    GATA1 is a master transcriptional regulator of the differentiation of several related myeloid blood cell types, including erythrocytes and megakaryocytes. Germ-line mutations that cause loss of full length GATA1, but allow for expression of the short isoform (GATA1s), are associated with defective erythropoiesis in a subset of patients with Diamond Blackfan Anemia. Despite extensive studies of GATA1s in megakaryopoiesis, the mechanism by which GATA1s fails to support normal erythropoiesis is not understood. In this study, we used global gene expression and chromatin occupancy analysis to compare the transcriptional activity of GATA1s to GATA1. We discovered that compared to GATA1, GATA1s is less able to activate the erythroid gene expression program and terminal differentiation in cells with dual erythroid-megakaryocytic differentiation potential. Moreover, we found that GATA1s bound to many of its erythroid-specific target genes less efficiently than full length GATA1. These results suggest that the impaired ability of GATA1s to promote erythropoiesis in DBA may be caused by failure to occupy erythroid-specific gene regulatory elements. PMID:25682601

  5. Generation of a High Number of Healthy Erythroid Cells from Gene-Edited Pyruvate Kinase Deficiency Patient-Specific Induced Pluripotent Stem Cells

    PubMed Central

    Garate, Zita; Quintana-Bustamante, Oscar; Crane, Ana M.; Olivier, Emmanuel; Poirot, Laurent; Galetto, Roman; Kosinski, Penelope; Hill, Collin; Kung, Charles; Agirre, Xabi; Orman, Israel; Cerrato, Laura; Alberquilla, Omaira; Rodriguez-Fornes, Fatima; Fusaki, Noemi; Garcia-Sanchez, Felix; Maia, Tabita M.; Ribeiro, Maria L.; Sevilla, Julian; Prosper, Felipe; Jin, Shengfang; Mountford, Joanne; Guenechea, Guillermo; Gouble, Agnes; Bueren, Juan A.; Davis, Brian R.; Segovia, Jose C.

    2015-01-01

    Summary Pyruvate kinase deficiency (PKD) is a rare erythroid metabolic disease caused by mutations in the PKLR gene. Erythrocytes from PKD patients show an energetic imbalance causing chronic non-spherocytic hemolytic anemia, as pyruvate kinase defects impair ATP production in erythrocytes. We generated PKD induced pluripotent stem cells (PKDiPSCs) from peripheral blood mononuclear cells (PB-MNCs) of PKD patients by non-integrative Sendai viral vectors. PKDiPSCs were gene edited to integrate a partial codon-optimized R-type pyruvate kinase cDNA in the second intron of the PKLR gene by TALEN-mediated homologous recombination (HR). Notably, we found allele specificity of HR led by the presence of a single-nucleotide polymorphism. High numbers of erythroid cells derived from gene-edited PKDiPSCs showed correction of the energetic imbalance, providing an approach to correct metabolic erythroid diseases and demonstrating the practicality of this approach to generate the large cell numbers required for comprehensive biochemical and metabolic erythroid analyses. PMID:26549847

  6. Generation of a High Number of Healthy Erythroid Cells from Gene-Edited Pyruvate Kinase Deficiency Patient-Specific Induced Pluripotent Stem Cells.

    PubMed

    Garate, Zita; Quintana-Bustamante, Oscar; Crane, Ana M; Olivier, Emmanuel; Poirot, Laurent; Galetto, Roman; Kosinski, Penelope; Hill, Collin; Kung, Charles; Agirre, Xabi; Orman, Israel; Cerrato, Laura; Alberquilla, Omaira; Rodriguez-Fornes, Fatima; Fusaki, Noemi; Garcia-Sanchez, Felix; Maia, Tabita M; Ribeiro, Maria L; Sevilla, Julian; Prosper, Felipe; Jin, Shengfang; Mountford, Joanne; Guenechea, Guillermo; Gouble, Agnes; Bueren, Juan A; Davis, Brian R; Segovia, Jose C

    2015-12-01

    Pyruvate kinase deficiency (PKD) is a rare erythroid metabolic disease caused by mutations in the PKLR gene. Erythrocytes from PKD patients show an energetic imbalance causing chronic non-spherocytic hemolytic anemia, as pyruvate kinase defects impair ATP production in erythrocytes. We generated PKD induced pluripotent stem cells (PKDiPSCs) from peripheral blood mononuclear cells (PB-MNCs) of PKD patients by non-integrative Sendai viral vectors. PKDiPSCs were gene edited to integrate a partial codon-optimized R-type pyruvate kinase cDNA in the second intron of the PKLR gene by TALEN-mediated homologous recombination (HR). Notably, we found allele specificity of HR led by the presence of a single-nucleotide polymorphism. High numbers of erythroid cells derived from gene-edited PKDiPSCs showed correction of the energetic imbalance, providing an approach to correct metabolic erythroid diseases and demonstrating the practicality of this approach to generate the large cell numbers required for comprehensive biochemical and metabolic erythroid analyses. PMID:26549847

  7. Effect of AGM and fetal liver-derived stromal cell lines on globin expression in adult baboon (P. anubis) bone marrow-derived erythroid progenitors.

    PubMed

    Lavelle, Donald; Vaitkus, Kestutis; Ruiz, Maria Armila; Ibanez, Vinzon; Kouznetsova, Tatiana; Saunthararajah, Yogen; Mahmud, Nadim; DeSimone, Joseph

    2012-01-01

    This study was performed to investigate the hypothesis that the erythroid micro-environment plays a role in regulation of globin gene expression during adult erythroid differentiation. Adult baboon bone marrow and human cord blood CD34+ progenitors were grown in methylcellulose, liquid media, and in co-culture with stromal cell lines derived from different developmental stages in identical media supporting erythroid differentiation to examine the effect of the micro-environment on globin gene expression. Adult progenitors express high levels of γ-globin in liquid and methylcellulose media but low, physiological levels in stromal cell co-cultures. In contrast, γ-globin expression remained high in cord blood progenitors in stromal cell line co-cultures. Differences in γ-globin gene expression between adult progenitors in stromal cell line co-cultures and liquid media required cell-cell contact and were associated with differences in rate of differentiation and γ-globin promoter DNA methylation. We conclude that γ-globin expression in adult-derived erythroid cells can be influenced by the micro-environment, suggesting new potential targets for HbF induction. PMID:22693559

  8. Effect of AGM and Fetal Liver-Derived Stromal Cell Lines on Globin Expression in Adult Baboon (P. anubis) Bone Marrow-Derived Erythroid Progenitors

    PubMed Central

    Lavelle, Donald; Vaitkus, Kestutis; Ruiz, Maria Armila; Ibanez, Vinzon; Kouznetsova, Tatiana; Saunthararajah, Yogen; Mahmud, Nadim; DeSimone, Joseph

    2012-01-01

    This study was performed to investigate the hypothesis that the erythroid micro-environment plays a role in regulation of globin gene expression during adult erythroid differentiation. Adult baboon bone marrow and human cord blood CD34+ progenitors were grown in methylcellulose, liquid media, and in co-culture with stromal cell lines derived from different developmental stages in identical media supporting erythroid differentiation to examine the effect of the micro-environment on globin gene expression. Adult progenitors express high levels of γ-globin in liquid and methylcellulose media but low, physiological levels in stromal cell co-cultures. In contrast, γ-globin expression remained high in cord blood progenitors in stromal cell line co-cultures. Differences in γ-globin gene expression between adult progenitors in stromal cell line co-cultures and liquid media required cell-cell contact and were associated with differences in rate of differentiation and γ-globin promoter DNA methylation. We conclude that γ-globin expression in adult-derived erythroid cells can be influenced by the micro-environment, suggesting new potential targets for HbF induction. PMID:22693559

  9. Association between Variants at BCL11A Erythroid-Specific Enhancer and Fetal Hemoglobin Levels among Sickle Cell Disease Patients in Cameroon: Implications for Future Therapeutic Interventions.

    PubMed

    Pule, Gift Dineo; Ngo Bitoungui, Valentina Josiane; Chetcha Chemegni, Bernard; Kengne, Andre Pascal; Antonarakis, Stylianos; Wonkam, Ambroise

    2015-10-01

    Variants in BCL11A were previously associated with fetal hemoglobin (HbF) levels among Cameroonian sickle cell disease (SCD) patients, however explaining only ∼2% of the variance. In the same patients, we have investigated the relationship between HbF and two SNPs in a BCL11A erythroid-specific enhancer (N=626). Minor allele frequencies in rs7606173 and rs1427407 were 0.42 and 0.24, respectively. Both variants were significantly associated with HbF levels (p=3.11e-08 and p=6.04e-06, respectively) and explained 8% and 6.2% variations, respectively. These data have confirmed a stronger effect on HbF of genomic variations at the BCL11A erythroid-specific enhancer among patients with SCD in Cameroon, the first report on a West African population. The relevance of these findings is of prime importance because the disruption of this enhancer would alter BCL11A expression in erythroid precursors and thus HbF expression, while sparing the induced functional challenges of any alterations on the expression of this transcription factor in non-erythroid lineages, thus providing an attractive approach for new treatment strategies of SCD. PMID:26393293

  10. Identification of Cell Type-Specific Differences in Erythropoietin Receptor Signaling in Primary Erythroid and Lung Cancer Cells.

    PubMed

    Merkle, Ruth; Steiert, Bernhard; Salopiata, Florian; Depner, Sofia; Raue, Andreas; Iwamoto, Nao; Schelker, Max; Hass, Helge; Wäsch, Marvin; Böhm, Martin E; Mücke, Oliver; Lipka, Daniel B; Plass, Christoph; Lehmann, Wolf D; Kreutz, Clemens; Timmer, Jens; Schilling, Marcel; Klingmüller, Ursula

    2016-08-01

    Lung cancer, with its most prevalent form non-small-cell lung carcinoma (NSCLC), is one of the leading causes of cancer-related deaths worldwide, and is commonly treated with chemotherapeutic drugs such as cisplatin. Lung cancer patients frequently suffer from chemotherapy-induced anemia, which can be treated with erythropoietin (EPO). However, studies have indicated that EPO not only promotes erythropoiesis in hematopoietic cells, but may also enhance survival of NSCLC cells. Here, we verified that the NSCLC cell line H838 expresses functional erythropoietin receptors (EPOR) and that treatment with EPO reduces cisplatin-induced apoptosis. To pinpoint differences in EPO-induced survival signaling in erythroid progenitor cells (CFU-E, colony forming unit-erythroid) and H838 cells, we combined mathematical modeling with a method for feature selection, the L1 regularization. Utilizing an example model and simulated data, we demonstrated that this approach enables the accurate identification and quantification of cell type-specific parameters. We applied our strategy to quantitative time-resolved data of EPO-induced JAK/STAT signaling generated by quantitative immunoblotting, mass spectrometry and quantitative real-time PCR (qRT-PCR) in CFU-E and H838 cells as well as H838 cells overexpressing human EPOR (H838-HA-hEPOR). The established parsimonious mathematical model was able to simultaneously describe the data sets of CFU-E, H838 and H838-HA-hEPOR cells. Seven cell type-specific parameters were identified that included for example parameters for nuclear translocation of STAT5 and target gene induction. Cell type-specific differences in target gene induction were experimentally validated by qRT-PCR experiments. The systematic identification of pathway differences and sensitivities of EPOR signaling in CFU-E and H838 cells revealed potential targets for intervention to selectively inhibit EPO-induced signaling in the tumor cells but leave the responses in erythroid

  11. RUNX1B Expression Is Highly Heterogeneous and Distinguishes Megakaryocytic and Erythroid Lineage Fate in Adult Mouse Hematopoiesis

    PubMed Central

    Draper, Julia E.; Sroczynska, Patrycja; Tsoulaki, Olga; Leong, Hui Sun; Fadlullah, Muhammad Z. H.; Miller, Crispin; Kouskoff, Valerie; Lacaud, Georges

    2016-01-01

    The Core Binding Factor (CBF) protein RUNX1 is a master regulator of definitive hematopoiesis, crucial for hematopoietic stem cell (HSC) emergence during ontogeny. RUNX1 also plays vital roles in adult mice, in regulating the correct specification of numerous blood lineages. Akin to the other mammalian Runx genes, Runx1 has two promoters P1 (distal) and P2 (proximal) which generate distinct protein isoforms. The activities and specific relevance of these two promoters in adult hematopoiesis remain to be fully elucidated. Utilizing a dual reporter mouse model we demonstrate that the distal P1 promoter is broadly active in adult hematopoietic stem and progenitor cell (HSPC) populations. By contrast the activity of the proximal P2 promoter is more restricted and its upregulation, in both the immature Lineage- Sca1high cKithigh (LSK) and bipotential Pre-Megakaryocytic/Erythroid Progenitor (PreMegE) populations, coincides with a loss of erythroid (Ery) specification. Accordingly the PreMegE population can be prospectively separated into “pro-erythroid” and “pro-megakaryocyte” populations based on Runx1 P2 activity. Comparative gene expression analyses between Runx1 P2+ and P2- populations indicated that levels of CD34 expression could substitute for P2 activity to distinguish these two cell populations in wild type (WT) bone marrow (BM). Prospective isolation of these two populations will enable the further investigation of molecular mechanisms involved in megakaryocytic/erythroid (Mk/Ery) cell fate decisions. Having characterized the extensive activity of P1, we utilized a P1-GFP homozygous mouse model to analyze the impact of the complete absence of Runx1 P1 expression in adult mice and observed strong defects in the T cell lineage. Finally, we investigated how the leukemic fusion protein AML1-ETO9a might influence Runx1 promoter usage. Short-term AML1-ETO9a induction in BM resulted in preferential P2 upregulation, suggesting its expression may be important to

  12. Identification of Cell Type-Specific Differences in Erythropoietin Receptor Signaling in Primary Erythroid and Lung Cancer Cells

    PubMed Central

    Salopiata, Florian; Depner, Sofia; Wäsch, Marvin; Böhm, Martin E.; Mücke, Oliver; Plass, Christoph; Lehmann, Wolf D.; Kreutz, Clemens; Timmer, Jens; Klingmüller, Ursula

    2016-01-01

    Lung cancer, with its most prevalent form non-small-cell lung carcinoma (NSCLC), is one of the leading causes of cancer-related deaths worldwide, and is commonly treated with chemotherapeutic drugs such as cisplatin. Lung cancer patients frequently suffer from chemotherapy-induced anemia, which can be treated with erythropoietin (EPO). However, studies have indicated that EPO not only promotes erythropoiesis in hematopoietic cells, but may also enhance survival of NSCLC cells. Here, we verified that the NSCLC cell line H838 expresses functional erythropoietin receptors (EPOR) and that treatment with EPO reduces cisplatin-induced apoptosis. To pinpoint differences in EPO-induced survival signaling in erythroid progenitor cells (CFU-E, colony forming unit-erythroid) and H838 cells, we combined mathematical modeling with a method for feature selection, the L1 regularization. Utilizing an example model and simulated data, we demonstrated that this approach enables the accurate identification and quantification of cell type-specific parameters. We applied our strategy to quantitative time-resolved data of EPO-induced JAK/STAT signaling generated by quantitative immunoblotting, mass spectrometry and quantitative real-time PCR (qRT-PCR) in CFU-E and H838 cells as well as H838 cells overexpressing human EPOR (H838-HA-hEPOR). The established parsimonious mathematical model was able to simultaneously describe the data sets of CFU-E, H838 and H838-HA-hEPOR cells. Seven cell type-specific parameters were identified that included for example parameters for nuclear translocation of STAT5 and target gene induction. Cell type-specific differences in target gene induction were experimentally validated by qRT-PCR experiments. The systematic identification of pathway differences and sensitivities of EPOR signaling in CFU-E and H838 cells revealed potential targets for intervention to selectively inhibit EPO-induced signaling in the tumor cells but leave the responses in erythroid

  13. Moving Toward Universal Health Coverage (UHC) to Achieve Inclusive and Sustainable Health Development: Three Essential Strategies Drawn From Asian Experience Comment on "Improving the World's Health Through the Post-2015 Development Agenda: Perspectives from Rwanda".

    PubMed

    Xu, Ye; Huang, Cheng; Colón-Ramos, Uriyoán

    2015-01-01

    Binagwaho and colleagues' perspective piece provided a timely reflection on the experience of Rwanda in achieving the Millennium Development Goals (MDGs) and a proposal of 5 principles to carry forward in post-2015 health development. This commentary echoes their viewpoints and offers three lessons for health policy reforms consistent with these principles beyond 2015. Specifically, we argue that universal health coverage (UHC) is an integrated solution to advance the global health development agenda, and the three essential strategies drawn from Asian countries' health reforms toward UHC are: (1) Public financing support and sequencing health insurance expansion by first extending health insurance to the extremely poor, vulnerable, and marginalized population are critical for achieving UHC; (2) Improved quality of delivered care ensures supply-side readiness and effective coverage; (3) Strategic purchasing and results-based financing creates incentives and accountability for positive changes. These strategies were discussed and illustrated with experience from China and other Asian economies. PMID:26673477

  14. Defects of protein production in erythroid cells revealed in a zebrafish Diamond-Blackfan anemia model for mutation in RPS19.

    PubMed

    Zhang, Y; Ear, J; Yang, Z; Morimoto, K; Zhang, B; Lin, S

    2014-01-01

    Diamond-Blackfan anemia (DBA) is a rare congenital red cell aplasia that classically presents during early infancy in DBA patients. Approximately, 25% of patients carry a mutation in the ribosomal protein (RP) S19 gene; mutations in RPS24, RPS17, RPL35A, RPL11, and RPL5 have been reported. How ribosome protein deficiency causes defects specifically to red blood cells in DBA has not been well elucidated. To genetically model the predominant ribosome defect in DBA, we generated an rps19 null mutant through the use of TALEN-mediated gene targeting in zebrafish. Molecular characterization of this mutant line demonstrated that rps19 deficiency reproduced the erythroid defects of DBA, including a lack of mature red blood cells and p53 activation. Notably, we found that rps19 mutants' production of globin proteins was significantly inhibited; however, globin transcript level was either increased or unaffected in rps19 mutant embryos. This dissociation of RNA/protein levels of globin genes was confirmed in another zebrafish DBA model with defects in rpl11. Using transgenic zebrafish with specific expression of mCherry in erythroid cells, we showed that protein production in erythroid cells was decreased when either rps19 or rpl11 was mutated. L-Leucine treatment alleviated the defects of protein production in erythroid cells and partially rescued the anemic phenotype in both rps19 and rpl11 mutants. Analysis of this model suggests that the decreased protein production in erythroid cells likely contributes to the blood-specific phenotype of DBA. Furthermore, the newly generated rps19 zebrafish mutant should serve as a useful animal model to study DBA. Our in vivo findings may provide clues for the future therapy strategy for DBA. PMID:25058426

  15. Identification of a novel erythroid-specific enhancer for the ALAS2 gene and its loss-of-function mutation which is associated with congenital sideroblastic anemia

    PubMed Central

    Kaneko, Kiriko; Furuyama, Kazumichi; Fujiwara, Tohru; Kobayashi, Ryoji; Ishida, Hiroyuki; Harigae, Hideo; Shibahara, Shigeki

    2014-01-01

    Erythroid-specific 5-aminolevulinate synthase (ALAS2) is the rate-limiting enzyme for heme biosynthesis in erythroid cells, and a missense mutation of the ALAS2 gene is associated with congenital sideroblastic anemia. However, the gene responsible for this form of anemia remains unclear in about 40% of patients. Here, we identify a novel erythroid-specific enhancer of 130 base pairs in the first intron of the ALAS2 gene. The newly identified enhancer contains a cis-acting element that is bound by the erythroid-specific transcription factor GATA1, as confirmed by chromatin immunoprecipitation analysis in vivo and by electrophoretic mobility shift assay in vitro. A promoter activity assay in K562 human erythroleukemia cells revealed that the presence of this 130-base pair region increased the promoter activity of the ALAS2 gene by 10–15-fold. Importantly, two mutations, each of which disrupts the GATA-binding site in the enhancer, were identified in unrelated male patients with congenital sideroblastic anemia, and the lower expression level of ALAS2 mRNA in bone marrow erythroblasts was confirmed in one of these patients. Moreover, GATA1 failed to bind to each mutant sequence at the GATA-binding site, and each mutation abolished the enhancer function on ALAS2 promoter activity in K562 cells. Thus, a mutation at the GATA-binding site in this enhancer may cause congenital sideroblastic anemia. These results suggest that the newly identified intronic enhancer is essential for the expression of the ALAS2 gene in erythroid cells. We propose that the 130-base pair enhancer region located in the first intron of the ALAS2 gene should be examined in patients with congenital sideroblastic anemia in whom the gene responsible is unknown. PMID:23935018

  16. Establishment of culturing system for ex-vivo expansion of angiogenic immature erythroid cells, and its application for treatment of patients with chronic severe lower limb ischemia.

    PubMed

    Oda, Masato; Toba, Ken; Ozawa, Takuya; Kato, Kiminori; Yanagawa, Takao; Ikarashi, Noboru; Takayama, Tsugumi; Suzuki, Tomoyasu; Hanawa, Haruo; Fuse, Ichiro; Nakata, Kou; Narita, Miwako; Takahashi, Masuhiro; Aizawa, Yoshifusa

    2010-09-01

    Angiogenesis therapy by bone marrow-mononuclear cell implantation (BMI) has been utilized. We found that erythroid cells played an essential role in angiogenesis by BMI. We then tried to establish a novel cell therapy by implantation of ex vivo expanded immature erythroblasts cultured from hematopoietic stem/precursor cells. Immature to mature erythroblasts were purified from human bone marrow, and mRNA expression were analyzed. Strongly expressed VEGF and PLGF in immature erythroid cells decreased according to erythroid maturation. To expand very immature erythroid cells, we established a two-step culturing system, i.e., bone marrow cells were cultured in the presence of Flt-3L, SCF and TPO for 7 days, and the cells were further cultured in the presence of SCF, IGF-I and EPO for an additional 7 days. The in vivo angiogenic effects of implantation of the ex vivo expanded cells were stronger than that of BMI in mouse limb ischemia model. Three patients with severe chronic lower limb ischemia accompanied by Burger's disease or collagen arteritis were enrolled in a pilot clinical trial of the novel cell therapy by transplantation of ex-vivo expanded immature erythroid cells. In the clinical trial, most clinical symptoms such as rest pain and skin ulcers improved in 4 weeks, and did not recur in the one-year follow-up. No adverse events were observed in any of the patients. Moreover this novel cell therapy required only a small amount of bone marrow collection. Further enrollment of patients with chronic severe lower limb ischemia is necessary to confirm the efficacy and safety of this novel cell therapy, and to estimate the necessary amount of bone marrow aspirate. PMID:20382155

  17. Effects of nucleoside analog incorporation on DNA binding to the DNA binding domain of the GATA-1 erythroid transcription factor.

    PubMed

    Foti, M; Omichinski, J G; Stahl, S; Maloney, D; West, J; Schweitzer, B I

    1999-02-01

    We investigate here the effects of the incorporation of the nucleoside analogs araC (1-beta-D-arabinofuranosylcytosine) and ganciclovir (9-[(1,3-dihydroxy-2-propoxy)methyl] guanine) into the DNA binding recognition sequence for the GATA-1 erythroid transcription factor. A 10-fold decrease in binding affinity was observed for the ganciclovir-substituted DNA complex in comparison to an unmodified DNA of the same sequence composition. AraC substitution did not result in any changes in binding affinity. 1H-15N HSQC and NOESY NMR experiments revealed a number of chemical shift changes in both DNA and protein in the ganciclovir-modified DNA-protein complex when compared to the unmodified DNA-protein complex. These changes in chemical shift and binding affinity suggest a change in the binding mode of the complex when ganciclovir is incorporated into the GATA DNA binding site. PMID:10037146

  18. Deficiency in the nuclear-related factor erythroid 2 transcription factor (Nrf1) leads to genetic instability.

    PubMed

    Oh, Diane H; Rigas, Diamanda; Cho, Ara; Chan, Jefferson Y

    2012-11-01

    Nuclear factor erythroid-derived 2-related factor 1 (Nrf1) regulates cellular stress response genes, and has also been suggested to play a role in other cellular processes. We previously demonstrated that hepatocyte-specific deletion of Nrf1 in mice resulted in spontaneous apoptosis, inflammation, and development of liver tumors. Here, we showed that both fibroblasts derived from Nrf1 null mouse embryos and fibroblasts expressing a conditional Nrf1 allele showed increased micronuclei and formation of abnormal nuclei. Lentiviral shRNA-mediated knockdown of Nrf1 in SAOS-2 cells also resulted in increased micronuclei, abnormal mitosis and multi-nucleated cells. Metaphase analyses showed increased aneuploidy in Nrf1(-/-) embryonic fibroblasts. Nuclear defects in Nrf1-deficient cells were associated with decreased expression of various genes encoding kinetochore and mitotic checkpoint proteins. Our findings suggest that Nrf1 may play a role in maintaining genomic integrity, and that Nrf1 dysregulation may induce tumorigenesis. PMID:22971132

  19. Fms-like tyrosine kinase 3 (Flt3) ligand depletes erythroid island macrophages and blocks medullar erythropoiesis in the mouse.

    PubMed

    Jacobsen, Rebecca N; Nowlan, Bianca; Brunck, Marion E; Barbier, Valerie; Winkler, Ingrid G; Levesque, Jean-Pierre

    2016-03-01

    The cytokines granulocyte colony-stimulating factor (G-CSF) and Flt3 ligand (Flt3-L) mobilize hematopoietic stem and progenitor cells into the peripheral blood of primates, humans, and mice. We recently reported that G-CSF administration causes a transient blockade of medullar erythropoiesis by suppressing erythroblastic island (EI) macrophages in the bone marrow. In the study described here, we investigated the effect of mobilizing doses of Flt3-L on erythropoiesis in mice in vivo. Similar to G-CSF, Flt3-L caused whitening of the bone marrow with significant reduction in the numbers of EI macrophages and erythroblasts. This was compensated by an increase in the numbers of EI macrophages and erythroblasts in the spleen. However, unlike G-CSF, Flt3-L had an indirect effect on EI macrophages, as it was not detected at the surface of EI macrophages or erythroid progenitors. PMID:26607596

  20. Annual Sustainability Report FY 2014. Incorporates NREL Site Sustainability Plan

    SciTech Connect

    Rukavina, Frank

    2015-07-01

    NREL's Sustainability Program is responsible for upholding all executive orders, federal regulations, U.S. Department of Energy (DOE) orders, and goals related to sustainable and resilient facility operations. But NREL continues to expand sustainable practices above and beyond the laboratory's regulations and requirements to ensure that the laboratory fulfills its mission into the future, leaves the smallest possible legacy footprint, and models sustainable operations and behaviors on national, regional, and local levels. The report, per the GRI reporting format, elaborates on multi-year goals relative to executive orders, achievements, and challenges; and success stories provide specific examples. A section called 'Sustaining NREL's Future Through Integration' provides insight into how NREL is successfully expanding the adoption of renewable energy technologies through integration.

  1. Sustainable developments

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Hundreds of diplomats, along with industry, finance, environment, and labor leaders from around the world met from April 20 to May 1 for the sixth session of the United Nations Commission for Sustainable Development (CSD), an annual follow-up conference to track the Agenda 21 program of action adopted at the 1992 Rio de Janeiro Earth Summit.During the session, which focused on freshwater management concerns and the role of industry in sustainable development, the participants discussed a number of issues about development and parity among northern and southern hemisphere countries.

  2. H-Ferritin Is Preferentially Incorporated by Human Erythroid Cells through Transferrin Receptor 1 in a Threshold-Dependent Manner

    PubMed Central

    Sakamoto, Soichiro; Kawabata, Hiroshi; Masuda, Taro; Uchiyama, Tatsuki; Mizumoto, Chisaki; Ohmori, Katsuyuki; Koeffler, H. Phillip; Kadowaki, Norimitsu; Takaori-Kondo, Akifumi

    2015-01-01

    Ferritin is an iron-storage protein composed of different ratios of 24 light (L) and heavy (H) subunits. The serum level of ferritin is a clinical marker of the body’s iron level. Transferrin receptor (TFR)1 is the receptor not only for transferrin but also for H-ferritin, but how it binds two different ligands and the blood cell types that preferentially incorporate H-ferritin remain unknown. To address these questions, we investigated hematopoietic cell-specific ferritin uptake by flow cytometry. Alexa Fluor 488-labeled H-ferritin was preferentially incorporated by erythroid cells among various hematopoietic cell lines examined, and was almost exclusively incorporated by bone marrow erythroblasts among human primary hematopoietic cells of various lineages. H-ferritin uptake by erythroid cells was strongly inhibited by unlabeled H-ferritin but was only partially inhibited by a large excess of holo-transferrin. On the other hand, internalization of labeled holo-transferrin by these cells was not inhibited by H-ferritin. Chinese hamster ovary cells lacking functional endogenous TFR1 but expressing human TFR1 with a mutated RGD sequence, which is required for transferrin binding, efficiently incorporated H-ferritin, indicating that TFR1 has distinct binding sites for H-ferritin and holo-transferrin. H-ferritin uptake by these cells required a threshold level of cell surface TFR1 expression, whereas there was no threshold for holo-transferrin uptake. The requirement for a threshold level of TFR1 expression can explain why among primary human hematopoietic cells, only erythroblasts efficiently take up H-ferritin. PMID:26441243

  3. Multiple cis elements regulate an alternative splicing event at 4.1R pre-mRNA during erythroid differentiation.

    PubMed

    Deguillien, M; Huang, S C; Morinière, M; Dreumont, N; Benz, E J; Baklouti, F

    2001-12-15

    The inclusion of exon 16 in the mature protein 4.1R messenger RNA (mRNA) is a critical event in red blood cell membrane biogenesis. It occurs during late erythroid development and results in inclusion of the 10-kd domain needed for stabilization of the spectrin/actin lattice. In this study, an experimental model was established in murine erythroleukemia cells that reproduces the endogenous exon 16 splicing patterns from a transfected minigene. Exon 16 was excluded in predifferentiated and predominantly included after induction. This suggests that the minigene contained exon and abutting intronic sequences sufficient for splicing regulation. A systematic analysis of the cis-acting regulatory sequences that reside within the exon and flanking introns was performed. Results showed that (1) the upstream intron of 4.1R pre-mRNA is required for exon recognition and it displays 2 enhancer elements, a distal element acting in differentiating cells and a proximal constitutive enhancer that resides within the 25 nucleotides preceding the acceptor site; (2) the exon itself contains a strong constitutive splicing silencer; (3) the exon has a weak 5' splice site; and (4) the downstream intron contains at least 2 splicing enhancer elements acting in differentiating cells, a proximal element at the vicinity of the 5' splice site, and a distal element containing 3 copies of the UGCAUG motif. These results suggest that the interplay between negative and positive elements may determine the inclusion or exclusion of exon 16. The activation of the enhancer elements in late erythroid differentiation may play an important role in the retention of exon 16. PMID:11739190

  4. Complete genomic organization of the human erythroid p55 gene (MPP1), a membrane-associated guanylate kinase homologue

    SciTech Connect

    Kim, A.C.; Metzenberg, A.B.; Sahr, K.E.

    1996-01-15

    Human p55 is an abundantly palmitoylated phosphoprotein of the erythroid membrane. It is the prototype of a newly discovered family of membrane-associated proteins termed MAGUKs (membrane-associated guanylate kinase homologues). The MAGUKs interact with the cytoskeleton and regulate cell proliferation, signaling pathways, and intercellular junctions. Here, we report the complete intron-exon map of the human erythroid p55 gene (HGMW-approved symbol MPP1). The structure of the p55 gene was determined from cosmid clones isolated from a cosmid library specific for the human X chromosome. There is a single copy of the p55 gene, composed of 12 exons and spanning approximately 28 kb in the q28 region of the human X chromosome. The exon sizes range from 69 (exon 5) to 203 bp (intron 2) to {approximately}14 kb (intron 1). The intron-exon boundaries conform to the donor/acceptor consensus sequence, GT-AG, for splice junctions. Several of the exon boundaries correspond to the boundaries of functional domains in the p55 protein. These domains include a SH3 motif and a region that binds to cytoskeletal protein 4.1. In addition, a comparison of the genomic and the primary structures of p55 reveals a highly conserved phosphotyrosine domain located between the protein 4.1 binding domain and the guanylate kinase domain. Finally, promoter activity measurements of the region immediately upstream of the p55 gene, which contains several cis-elements commonly found in housekeeping genes, suggest that a CpG island may be associated with the p55 gene expression in vivo. 42 refs., 5 figs., 1 tab.

  5. H-Ferritin Is Preferentially Incorporated by Human Erythroid Cells through Transferrin Receptor 1 in a Threshold-Dependent Manner.

    PubMed

    Sakamoto, Soichiro; Kawabata, Hiroshi; Masuda, Taro; Uchiyama, Tatsuki; Mizumoto, Chisaki; Ohmori, Katsuyuki; Koeffler, H Phillip; Kadowaki, Norimitsu; Takaori-Kondo, Akifumi

    2015-01-01

    Ferritin is an iron-storage protein composed of different ratios of 24 light (L) and heavy (H) subunits. The serum level of ferritin is a clinical marker of the body's iron level. Transferrin receptor (TFR)1 is the receptor not only for transferrin but also for H-ferritin, but how it binds two different ligands and the blood cell types that preferentially incorporate H-ferritin remain unknown. To address these questions, we investigated hematopoietic cell-specific ferritin uptake by flow cytometry. Alexa Fluor 488-labeled H-ferritin was preferentially incorporated by erythroid cells among various hematopoietic cell lines examined, and was almost exclusively incorporated by bone marrow erythroblasts among human primary hematopoietic cells of various lineages. H-ferritin uptake by erythroid cells was strongly inhibited by unlabeled H-ferritin but was only partially inhibited by a large excess of holo-transferrin. On the other hand, internalization of labeled holo-transferrin by these cells was not inhibited by H-ferritin. Chinese hamster ovary cells lacking functional endogenous TFR1 but expressing human TFR1 with a mutated RGD sequence, which is required for transferrin binding, efficiently incorporated H-ferritin, indicating that TFR1 has distinct binding sites for H-ferritin and holo-transferrin. H-ferritin uptake by these cells required a threshold level of cell surface TFR1 expression, whereas there was no threshold for holo-transferrin uptake. The requirement for a threshold level of TFR1 expression can explain why among primary human hematopoietic cells, only erythroblasts efficiently take up H-ferritin. PMID:26441243

  6. Human Erythroid 5-Aminolevulinate Synthase Mutations Associated with X-Linked Protoporphyria Disrupt the Conformational Equilibrium and Enhance Product Release.

    PubMed

    Fratz, Erica J; Clayton, Jerome; Hunter, Gregory A; Ducamp, Sarah; Breydo, Leonid; Uversky, Vladimir N; Deybach, Jean-Charles; Gouya, Laurent; Puy, Hervé; Ferreira, Gloria C

    2015-09-15

    Regulation of 5-aminolevulinate synthase (ALAS) is at the origin of balanced heme production in mammals. Mutations in the C-terminal region of human erythroid-specific ALAS (hALAS2) are associated with X-linked protoporphyria (XLPP), a disease characterized by extreme photosensitivity, with elevated blood concentrations of free protoporphyrin IX and zinc protoporphyrin. To investigate the molecular basis for this disease, recombinant hALAS2 and variants of the enzyme harboring the gain-of-function XLPP mutations were constructed, purified, and analyzed kinetically, spectroscopically, and thermodynamically. Enhanced activities of the XLPP variants resulted from increases in the rate at which the product 5-aminolevulinate (ALA) was released from the enzyme. Circular dichroism spectroscopy revealed that the XLPP mutations altered the microenvironment of the pyridoxal 5'-phosphate cofactor, which underwent further and specific alterations upon succinyl-CoA binding. Transient kinetic analyses of the variant-catalyzed reactions and protein fluorescence quenching upon binding of ALA to the XLPP variants demonstrated that the protein conformational transition step associated with product release was predominantly affected. Of relevance is the fact that XLPP could also be modeled in cell culture. We propose that (1) the XLPP mutations destabilize the succinyl-CoA-induced hALAS2 closed conformation and thus accelerate ALA release, (2) the extended C-terminus of wild-type mammalian ALAS2 provides a regulatory role that allows for allosteric modulation of activity, thereby controlling the rate of erythroid heme biosynthesis, and (3) this control is disrupted in XLPP, resulting in porphyrin accumulation. PMID:26300302

  7. The SOD1 transgene expressed in erythroid cells alleviates fatal phenotype in congenic NZB/NZW-F1 mice.

    PubMed

    Otsuki, Noriyuki; Konno, Tasuku; Kurahashi, Toshihiro; Suzuki, Saori; Lee, Jaeyong; Okada, Futoshi; Iuchi, Yoshihito; Homma, Takujiro; Fujii, Junichi

    2016-07-01

    Oxidative stress due to a superoxide dismutase 1 (SOD1) deficiency causes anemia and autoimmune responses, which are phenotypically similar to autoimmune hemolytic anemia (AIHA) and systemic lupus erythematosus (SLE) in C57BL/6 mice and aggravates AIHA pathogenesis in New Zealand black (NZB) mice. We report herein on an evaluation of the role of reactive oxygen species (ROS) in a model mouse with inherited SLE, that is, F1 mice of the NZB × New Zealand white (NZW) strain. The ROS levels within red blood cells (RBCs) of the F1 mice were similar to the NZW mice but lower compared to the NZB mice throughout adult period. Regarding SLE pathogenesis, we examined the effects of an SOD1 deficiency or the overexpression of human SOD1 in erythroid cells by establishing corresponding congenic F1 mice. A SOD1 deficiency caused an elevation in ROS production, methemoglobin content, and hyperoxidation of peroxiredoxin in RBC of the F1 mice, which were all consistent with elevated oxidative stress. However, while the overexpression of human SOD1 in erythroid cells extended the life span of the congenic F1 mice, the SOD1 deficiency had no effect on life span compared to wild-type F1 mice. It is generally recognized that NZW mice possess a larval defect in the immune system and that NZB mice trigger an autoimmune reaction in the F1 mice. Our results suggest that the oxidative insult originated from the NZB mouse background has a functional role in triggering an aberrant immune reaction, leading to fatal responses in F1 mice. PMID:27080108

  8. Achieving Energy Efficiency Through Real-Time Feedback

    SciTech Connect

    Nesse, Ronald J.

    2011-09-01

    Through the careful implementation of simple behavior change measures, opportunities exist to achieve strategic gains, including greater operational efficiencies, energy cost savings, greater tenant health and ensuing productivity and an improved brand value through sustainability messaging and achievement.

  9. The road to sustainability

    SciTech Connect

    Sarrao, John L; Crabtree, George

    2009-01-01

    Sustainability is the hottest topic in energy research today, but what does it actually mean? George Crabtree and John Sarrao describe what makes a technology sustainable, and outline the materials-science challenges standing between us and clean, long-lasting energy. Although most people agree that more-sustainable energy technologies are desirable, they often find it harder to agree on exactly how sustainable these technologies need to be, and even precisely what is meant by sustainability. To clarify the debate, we suggest three criteria for sustainability, each of which captures a different feature of the problem. While we do not have the lUxury of achieving full sustainability for all of our next-generation energy technologies, we can use these definitions to select our strategic sustainability targets and track our progress toward achieving them. As will become clear, the most sustainable energy technologies require the most challenging fundamental science breakthroughs. The first criterion for sustainability is 'lasts a long time'. This quality has been a feature of many energy sources we have used historically, including wood in ancient times and oil throughout most of the 20th century. The definition of 'long time' is, of course, relative: the world's demand for energy long ago outpaced the ability of wood to supply it, and the production of oil is likely to peak sometime within the next few decades. Substantial reductions in the rate of oil consumption through higher-efficiency processes can significantly impact on how long non-renewable resources last. In applying the 'long time' criterion, we need to distinguish between energy sources that are effectively limitless and those that are finite but, for the moment, adequate. The second criterion for sustainability is 'does no harm'. Burning fossil fuels releases pollutants such as sulphur and mercury that endanger human health, as well as greenhouse gases like carbon dioxide that threaten climate stability

  10. Exergy sustainability.

    SciTech Connect

    Robinett, Rush D. III; Wilson, David Gerald; Reed, Alfred W.

    2006-05-01

    Exergy is the elixir of life. Exergy is that portion of energy available to do work. Elixir is defined as a substance held capable of prolonging life indefinitely, which implies sustainability of life. In terms of mathematics and engineering, exergy sustainability is defined as the continuous compensation of irreversible entropy production in an open system with an impedance and capacity-matched persistent exergy source. Irreversible and nonequilibrium thermodynamic concepts are combined with self-organizing systems theories as well as nonlinear control and stability analyses to explain this definition. In particular, this paper provides a missing link in the analysis of self-organizing systems: a tie between irreversible thermodynamics and Hamiltonian systems. As a result of this work, the concept of ''on the edge of chaos'' is formulated as a set of necessary and sufficient conditions for stability and performance of sustainable systems. This interplay between exergy rate and irreversible entropy production rate can be described as Yin and Yang control: the dialectic synthesis of opposing power flows. In addition, exergy is shown to be a fundamental driver and necessary input for sustainable systems, since exergy input in the form of power is a single point of failure for self-organizing, adaptable systems.

  11. Y-12 Site Sustainability Plan

    SciTech Connect

    Spencer, Charles G

    2012-12-01

    The accomplishments to date and the long-range planning of the Y-12 Energy Management and Sustainability and Stewardship programs support the U.S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) vision for a commitment to energy effi ciency and sustainability and to achievement of the Guiding Principles. Specifi cally, the Y-12 vision is to support the Environment, Safety and Health Policy and the DOE Strategic Sustainability Performance Plan, while promoting overall sustainability and reduction of greenhouse gas emissions. The mission of the Y-12 Energy Management program is to incorporate energy-effi cient technologies site-wide and to position Y-12 to meet NNSA energy requirement needs through 2025 and beyond. The plan addresses greenhouse gases, buildings, fleet management, water use, pollution prevention, waste reduction, sustainable acquisition, electronic stewardship and data centers, site innovation and government-wide support.

  12. Is Sustainability Possible? A Review and Commentary on Empirical Studies of Program Sustainability

    ERIC Educational Resources Information Center

    Scheirer, Mary Ann

    2005-01-01

    An important final step in the life cycles of programs and their evaluation involves assessing new programs' or innovations' sustainability. This review and synthesis of 19 empirical studies of the sustainability of American and Canadian health-related programs examines the extent of sustainability achieved and summarizes factors contributing to…

  13. Teaching Sustainability/Teaching Sustainably

    ERIC Educational Resources Information Center

    Bartels, Kirsten Allen, Ed.; Parker, Kelly A., Ed.

    2011-01-01

    Over the coming decades, every academic discipline will have to respond to the paradigm of more sustainable life practices because students will be living in a world challenged by competition for resources and climate change, and will demand that every academic discipline demonstrate substantial and corresponding relevance. This book takes as its…

  14. Y-12 Site Sustainability Plan

    SciTech Connect

    Sherry, T D; Kohlhorst, D P; Little, S K

    2011-12-01

    The accomplishments to date and the long-range planning of the Y-12 Energy Management and Sustainability and Stewardship programs support the DOE and the National Nuclear Security Administration (NNSA) vision for a commitment to energy efficiency and sustainability and to achievement of the Guiding Principles. Specifically, the Y-12 vision is to support the Environment, Safety and Health Policy and the DOE Strategic Sustainability Performance Plan (SSPP) while promoting overall sustainability and reduction of greenhouse gas (GHG) emissions. Table ES.2 gives a comprehensive overview of Y-12's performance status and planned actions. B&W Y-12's Energy Management mission is to incorporate renewable energy and energy efficient technologies site-wide and to position Y-12 to meet NNSA energy requirement needs through 2025 and beyond. During FY 2011, the site formed a sustainability team (Fig. ES.1). The sustainability team provides a coordinated approach to meeting the various sustainability requirements and serves as a forum for increased communication and consistent implementation of sustainability activities at Y-12. The sustainability team serves as an information exchange mechanism to promote general awareness of sustainability information, while providing a system to document progress and to identify resources. These resources are necessary to implement activities that support the overall goals of sustainability, including reducing the use of resources and conserving energy. Additionally, the team's objectives include: (1) Foster a Y-12-wide philosophy to conserve resources; (2) Reduce the impacts of production operations in a cost-effective manner; (3) Increase materials recycling; (4) Use a minimum amount of energy and fuel; (5) Create a minimum of waste and pollution in achieving Y-12-strategic objectives; (6) Develop and implement techniques, technologies, process modifications, and programs that support sustainable acquisition; (7) Minimize the impacts to

  15. GIS-mapping of environmental assessment of the territories in the region of intense activity for the oil and gas complex for achievement the goals of the Sustainable Development (on the example of Russia)

    NASA Astrophysics Data System (ADS)

    Yermolaev, Oleg

    2014-05-01

    The uniform system of complex scientific-reference ecological-geographical should act as a base for the maintenance of the Sustainable Development (SD) concept in the territories of the Russian Federation subjects or certain regions. In this case, the assessment of the ecological situation in the regions can be solved by the conjugation of the two interrelated system - the mapping and the geoinformational. The report discusses the methodological aspects of the Atlas-mapping for the purposes of SD in the regions of Russia. The Republic of Tatarstan viewed as a model territory where a large-scale oil-gas complex "Tatneft" PLC works. The company functions for more than 60 years. Oil fields occupy an area of more than 38 000 km2; placed in its territory about 40 000 oil wells, more than 55 000 km of pipelines; more than 3 billion tons of oil was extracted. Methods for to the structure and requirements for the Atlas's content were outlined. The approaches to mapping of "an ecological dominant" of SD conceptually substantiated following the pattern of a large region of Russia. Several trends of thematically mapping were suggested to be distinguished in the Atlas's structure: • The background history of oil-fields mine working; • The nature preservation technologies while oil extracting; • The assessment of natural conditions of a humans vital activity; • Unfavorable and dangerous natural processes and phenomena; • The anthropogenic effect and environmental surroundings change; • The social-economical processes and phenomena. • The medical-ecological and geochemical processes and phenomena; Within these groups the other numerous groups can distinguished. The maps of unfavorable and dangerous processes and phenomena subdivided in accordance with the types of processes - of endogenous and exogenous origin. Among the maps of the anthropogenic effects on the natural surroundings one can differentiate the maps of the influence on different nature's spheres

  16. Sustainable NREL

    ScienceCinema

    None

    2013-05-29

    The National Renewable Energy Laboratory prides itself on not only advancing the renewable energy, but "walking the talk" when it comes to sustainable practices. "When you look at our laboratories, you will see energy efficiency in action, but you'll also see renewable energy. We walk the walk and we talk the talk. We believe in it and we want to live it also."

  17. Sustainable NREL

    SciTech Connect

    2011-01-01

    The National Renewable Energy Laboratory prides itself on not only advancing the renewable energy, but "walking the talk" when it comes to sustainable practices. "When you look at our laboratories, you will see energy efficiency in action, but you'll also see renewable energy. We walk the walk and we talk the talk. We believe in it and we want to live it also."

  18. Why Sustainable Practices Matter.

    PubMed

    Rich, Jeff

    2016-01-01

    Sustainable thinking provides an opportunity to create new value to the mission of health care, rather than settling for less. Success stories and case studies exist, which if replicated can have an enormous positive effect. The future holds promise. Many health care organizations are signing up with efforts such as the Healthier Hospitals initiative, a program of the Practice Greenhealth membership organization for sustainable health care, to set new standards and learn more about methods to reduce the environmental footprint and negative health effects from the delivery of care to their communities. Providing safe and affordable care to patients and their families must remain paramount in the decisions that are made, but good environmental stewardship can be achieved. Setting organizational goals holds the key to finding the optimal balance. PMID:27333682

  19. [Diverse sustainability--sustainable diversity].

    PubMed

    Schmeling-Kludas, Christoph; Koch-Gromus, Uwe

    2011-08-01

    In spite of its plenitude, the scientific works of the important German psychologist Ernst August Dölle (1898-1972) are little adapted till today, mostly they are being reduced to his studies about dichotomy and duplicity. But based on his diaries of the year 1968, the authors can verify without doubt, that Dölle far ahead of his time, carried on research about sustainability and diversity. He was the first scientist worldwide to connect these two concepts. PMID:21837611

  20. Graded Achievement, Tested Achievement, and Validity

    ERIC Educational Resources Information Center

    Brookhart, Susan M.

    2015-01-01

    Twenty-eight studies of grades, over a century, were reviewed using the argument-based approach to validity suggested by Kane as a theoretical framework. The review draws conclusions about the meaning of graded achievement, its relation to tested achievement, and changes in the construct of graded achievement over time. "Graded…

  1. Sustainable Astronomy

    NASA Astrophysics Data System (ADS)

    Blaha, C.; Goetz, J.; Johnson, T.

    2011-09-01

    Through our International Year of Astronomy outreach effort, we established a sustainable astronomy program and curriculum in the Northfield, Minnesota community. Carleton College offers monthly open houses at Goodsell Observatory and donated its recently "retire" observing equipment to local schools. While public evenings continue to be popular, the donated equipment was underutilized due to a lack of trained student observing assistants. With sponsorship from NASA's IYA Student Ambassador program, the sustainable astronomy project began in 2009 to generate greater interest in astronomy and train middle school and high school students as observing assistants. Carleton physics majors developed curricular materials and instituted regular outreach programs for grades 6-12. The Northfield High School Astronomy Club was created, and Carleton undergraduates taught high school students how to use telescopes and do CCD imaging. During the summer of 2009, Carleton students began the Young Astronomers Summer Experience (YASE) program for middle school students and offered a two-week, astronomy-rich observing and imaging experience at Goodsell Observatory. In concert with NASA's Summer of Innovation initiative, the YASE program was offered again in 2010 and engaged a new group of local middle school students in hands-on scientific experiments and observing opportunities. Members of the high school astronomy club now volunteer as observing assistants in the community and graduates of the YASE programs are eager to continue observing as members of a public service astronomy club when they enter the Northfield High School. These projects are training future scientists and will sustain the public's interest in astronomy long after the end of IYA 2009.

  2. Genetic manipulation of RPS5 gene expression modulates the initiation of commitment of MEL cells to erythroid maturation: Implications in understanding ribosomopathies.

    PubMed

    Vizirianakis, Ioannis S; Papachristou, Eleni T; Andreadis, Panagiotis; Zopounidou, Elena; Matragkou, Christina N; Tsiftsoglou, Asterios S

    2015-07-01

    Impairment of ribosome biogenesis contributes to the molecular pathophysiology of ribosomopathies by deregulating cell-lineage specific proliferation, differentiation and apoptosis decisions of haematopoietic progenitor cells. Here, using pro-erythroblast-like murine erythroleukemia (MEL) cells, a model system of erythroid maturation, we aimed to investigate whether genetic manipulation of RPS5 expression affects the capacity of cells to grow and differentiate in culture. Parental MEL cells stably transfected with full length RPS5 cDNA in sense (MEL-C14 culture) or antisense (MEL-antisenseRPS5 culture) orientation, as well as MEL cells transiently transfected with siRNAs specific for RPS5 gene silencing (MEL-RPS5siRNA culture) were assessed for their ability to fully execute their erythroid maturation program in culture. The data obtained thus far indicate that: a) MEL-antisenseRPS5 exhibit a pronounced delay in the initiation of differentiation, as well as an impairment of commitment, since the continuous presence of the inducer in culture is required for the cells to fully execute their erythroid maturation program. b) RNAi-mediating silencing of RPS5 gene expression resulted in the inability of MEL cells to differentiate; however, when these cells were allowed to recapitulate normal RPS5 gene expression levels they regained their differentiation capacity by accumulating high proportion of erythroid mature cells. c) Interestingly the latter, is accompanied by morphological changes of cells and an impairment of their proliferation and apoptosis potential. Such data for the first time correlate the RPS5 gene expression levels with the differentiation capacity of MEL cells in vitro, a fact that might also have implications in understanding ribosomopathies. PMID:25998414

  3. Effect of Tumor Necrosis Factor-Alpha on Erythropoietin- and Erythropoietin Receptor-Induced Erythroid Progenitor Cell Proliferation in β-Thalassemia/Hemoglobin E Patients

    PubMed Central

    Tanyong, Dalina I; Panichob, Prapaporn; Kheansaard, Wasinee; Fucharoen, Suthat

    2015-01-01

    Objective: Thalassemia is one of the genetic diseases that cause anemia and ineffective erythropoiesis. Increased levels of several inflammatory cytokines have been reported in β-thalassemia and might contribute to ineffective erythropoiesis. However, the mechanism by which tumor necrosis factor-alpha (TNF-α) is involved in ineffective erythropoiesis in thalassemic patients remains unclear. The objective of this study is to investigate the effect of TNF-α on the erythropoietin (EPO) and erythropoietin receptor (EPOR) expression involved in proliferation of β-thalassemia/hemoglobin (Hb) E erythroid progenitor cells compared with cells from healthy subjects. Materials and Methods: CD34-positive cells were isolated from heparinized blood by using the EasySep® CD34 selection kit. Cells were then cultured with suitable culture medium in various concentrations of EPO for 14 days. The effect of TNF-α on percent cell viability was analyzed by trypan blue staining. In addition, the percentage of apoptosis and levels of EPOR protein were measured by flow cytometry. Results: Upon EPO treatment, a higher cell number was observed for erythroid progenitor cells from both healthy participants and β-thalassemia/Hb E patients. However, a reduction of apoptosis was found in EPO-treated cells especially for β-thalassemia/Hb E patients. Interestingly, TNF-α caused higher levels of cell apoptosis and lower levels of EPOR protein in thalassemic erythroid progenitor cells. Conclusion: TNF-α caused a reduction in the level of EPOR protein and EPO-induced erythroid progenitor cell proliferation. It is possible that TNF-α could be involved in the mechanism of ineffective erythropoiesis in β-thalassemia/Hb E patients. PMID:26376749

  4. Hydrogen Sulfide Levels and Nuclear Factor-Erythroid 2-Related Factor 2 (NRF2) Activity Are Attenuated in the Setting of Critical Limb Ischemia (CLI)

    PubMed Central

    Islam, Kazi N; Polhemus, David J; Donnarumma, Erminia; Brewster, Luke P; Lefer, David J

    2015-01-01

    Background Cystathionine γ-lyase, cystathionine β-synthase, and 3-mercaptopyruvate sulfurtransferase are endogenous enzymatic sources of hydrogen sulfide (H2S). Functions of H2S are mediated by several targets including ion channels and signaling proteins. Nuclear factor-erythroid 2-related factor 2 is responsible for the expression of antioxidant response element–regulated genes and is known to be upregulated by H2S. We examined the levels of H2S, H2S-producing enzymes, and nuclear factor-erythroid 2-related factor 2 activation status in skeletal muscle obtained from critical limb ischemia (CLI) patients. Methods and Results Gastrocnemius tissues were attained postamputation from human CLI and healthy control patients. We found mRNA and protein levels of cystathionine γ-lyase, cystathionine β-synthase, and 3-mercaptopyruvate sulfurtransferase were significantly decreased in skeletal muscle of CLI patients as compared to control. H2S and sulfane sulfur levels were significantly decreased in skeletal muscle of CLI patients. We also observed significant reductions in nuclear factor-erythroid 2-related factor 2 activation as well as antioxidant proteins, such as Cu, Zn-superoxide dismutase, catalase, and glutathione peroxidase in skeletal muscle of CLI patients. Biomarkers of oxidative stress, such as malondialdehyde and protein carbonyl formation, were significantly increased in skeletal muscle of CLI patients as compared to healthy controls. Conclusions The data demonstrate that H2S bioavailability and nuclear factor-erythroid 2-related factor 2 activation are both attenuated in CLI tissues concomitant with significantly increased oxidative stress. Reductions in the activity of H2S-producing enzymes may contribute to the pathogenesis of CLI. PMID:25977470

  5. Disruption of the 5S RNP-Mdm2 interaction significantly improves the erythroid defect in a mouse model for Diamond-Blackfan anemia.

    PubMed

    Jaako, P; Debnath, S; Olsson, K; Zhang, Y; Flygare, J; Lindström, M S; Bryder, D; Karlsson, S

    2015-11-01

    Diamond-Blackfan anemia (DBA) is a congenital erythroid hypoplasia caused by haploinsufficiency of genes encoding ribosomal proteins (RPs). Perturbed ribosome biogenesis in DBA has been shown to induce a p53-mediated ribosomal stress response. However, the mechanisms of p53 activation and its relevance for the erythroid defect remain elusive. Previous studies have indicated that activation of p53 is caused by the inhibition of mouse double minute 2 (Mdm2), the main negative regulator of p53, by the 5S ribonucleoprotein particle (RNP). Meanwhile, it is not clear whether this mechanism solely mediates the p53-dependent component found in DBA. To approach this question, we crossed our mouse model for RPS19-deficient DBA with Mdm2(C305F) knock-in mice that have a disrupted 5S RNP-Mdm2 interaction. Upon induction of the Rps19 deficiency, Mdm2(C305F) reversed the p53 response and improved expansion of hematopoietic progenitors in vitro, and ameliorated the anemia in vivo. Unexpectedly, disruption of the 5S RNP-Mdm2 interaction also led to selective defect in erythropoiesis. Our findings highlight the sensitivity of erythroid progenitor cells to aberrations in p53 homeostasis mediated by the 5S RNP-Mdm2 interaction. Finally, we provide evidence indicating that physiological activation of the 5S RNP-Mdm2-p53 pathway may contribute to functional decline of the hematopoietic system in a cell-autonomous manner over time. PMID:25987256

  6. The transactivation domain AF-2 but not the DNA-binding domain of the estrogen receptor is required to inhibit differentiation of avian erythroid progenitors.

    PubMed

    von Lindern, M; Boer, L; Wessely, O; Parker, M; Beug, H

    1998-02-01

    Earlier work demonstrated that an activated estrogen receptor (ER) is required for long-term self-renewal of c-ErbB-expressing avian erythroid progenitors. Here, we demonstrate that activation of the ER does not only arrest or retard differentiation of early progenitors but that it affects erythroid differentiation at all stages of erythroid maturation. A search for genes whose expression is affected by the ER showed that the 17beta-estradiol-activated receptor suppressed the differentiation-associated up-regulation of Gata-1, SCL-1, and globin genes in partially mature cells. In the same cells, the expression of carbonic anhydrase II (CAII) and histone H5 was enhanced. This led to premature expression of CAII, a possible explanation for the toxic effects of overexpressed ER. Repression specifically required the transactivation domain AF-2, but neither an intact DNA-binding domain (DBD) nor the AF-1 domain. The transcriptional activation of CAII, however, required both an intact AF-2 and a functional DBD. The requirement for the AF-2, but not the DBD, suggested that the ER may compete with other nuclear hormone receptors for transcriptional coactivators that bind AF-2, a domain well conserved within this family of transcription factors. We show, however, that this model does not apply for the most likely candidate, the avian thyroid hormone receptor. PMID:9482667

  7. Desensitization to hydroxycarbamide following long-term treatment of thalassaemia intermedia as observed in vivo and in primary erythroid cultures from treated patients.

    PubMed

    Rigano, Paolo; Pecoraro, Alice; Calzolari, Roberta; Troia, Antonio; Acuto, Santina; Renda, Disma; Pantalone, Gaetano Restivo; Maggio, Aurelio; Di Marzo, Rosalba

    2010-12-01

    Hydroxycarbamide (HC) is a pharmacological agent capable of stimulating fetal haemoglobin (HbF) production during adult life. High levels of HbF may ameliorate the clinical course of β-thalassaemia and sickle cell disease. The efficacy of HC for the treatment of thalassaemia major and thalassaemia intermedia is variable. Although an increase of HbF has been observed in most patients, only some patients experience significant improvement in total haemoglobin levels. This study aimed to determine the effectiveness and safety of short- (1 year) and long-term (mean follow-up 68 months) HC treatment in 24 thalassaemia intermedia patients. Additionally, we evaluated if primary erythroid progenitor cells cultured from treated patients responded to HC treatment in a manner similar to that observed in vivo. Our results confirm a good response to HC after a short-term follow-up in 70% of thalassaemia intermedia patients and a reduction of clinical response in patients with a long follow-up. Erythroid cultures obtained from patients during treatment reproduced the observed in vivo response. Interestingly, haematopoietic stem cells from long-term treated patients showed reduced ability to develop into primary erythroid cultures some months before the reduction of the 'in vivo' response. The mechanism of this loss of response to HC remains to be determined. PMID:20955403

  8. Augmentation of erythroid burst formation by the addition of thymocytes and other myelo-lymphoid cells.

    PubMed

    Kanamaru, A; Durban, E; Gallagher, M T; Miller, S C; Trentin, J J

    1980-08-01

    Bone marrow from barrier-sustained specific pathogen-free (SPF) CBA and C57BL/6 mice gave relatively low numbers of BFU-E colonies in methylcellulose culture, as compared to conventional mice. Addition of thymocytes to the marrow cultures increased the yield of BFU-E colonies more than fourfold in SPF mice but only 1.5-fold in conventional mice. Colony size was also increased. Increased yield of BFU-E colonies was also obtained by co-culture of bone marrow with lymph node cells or with bone marrow or spleen cells from 900R whole-body irradiated mice. The effect appeared to be cellular rather than humoral. It was not reproduced by conditioned medium from thymus or pokeweed mitogen stimulated spleen cells. The helper effect of thymus cells was eliminated or reduced by freezing and thawing, or by 48 hours of incubation after irradiation. Treatment of bone marrow cells in vitro with anti-theta serum and complement did not decrease the number of BFU-E colonies. The putative helper cells appear not to be T cells, were non-adherent to the plastic culture dish, and were cortisone resistant and radioresistant. The low BFU-E colony yield from SPF mouse marrow is presumed to be largely the result of deficiency of these non-T helper cells in SPF bone marrow, rather than of BFU-E progenitor cells. PMID:6447706

  9. Radioprotection of mice with interleukin-1: Relationship to the number of erythroid and granulocyte-macrophage colony-forming cells

    SciTech Connect

    Schwartz, G.N.; Patchen, M.L.; Neta, R.; MacVittie, T.J.

    1990-01-01

    This report presents the results of an investigation of changes in the number of erythroid and granulocyte-macrophage colony forming cells (GM-CFC) that had occurred in tissues of normal B6D2F1 mice 20 h after administration of a radioprotective dose (150 ng) of human recombinant interleukin-1 (rIL-1). Neutrophilia in the peripheral blood and changes in the tissue distribution of GM-CFC demonstrated that cells were mobilized from the bone marrow in response to rIL-1 injection. For example, 20 h after rIL-1 injection marrow GM-CFC numbers were 80% of the numbers in bone marrow from saline-injected mice. Associated with this decrease there was a twofold increase in the number of peripheral blood and splenic GM-CFC. Also, as determined by hydroxyurea injection, there was an increase in the number of GM-CFC in S phase of the cell cycle in the spleen, but not in the bone marrow. Data in this report suggest that when compared to the spleen, stimulation of granulopoiesis after rIL-1 injection is delayed in the bone marrow.

  10. The effects of erythropoietin signaling on telomerase regulation in non-erythroid malignant and non-malignant cells

    SciTech Connect

    Uziel, Orit; Kanfer, Gil; Beery, Einat; Yelin, Dana; Shepshelovich, Daniel; Bakhanashvili, Mary; Nordenberg, Jardena; Lahav, Meir

    2014-07-18

    Highlights: • We assumed that some of erythropoietin adverse effects may be mediated by telomerase activity. • EPO administration increased telomerase activity, cells proliferation and migration. • The inhibition of telomerase modestly repressed the proliferative effect of erythropoietin. • Telomere shortening caused by long term inhibition of the enzyme totally abolished that effect. • This effect was mediated via the Lyn–AKT axis and not by the canonical JAK2–STAT pathway. - Abstract: Treatment with erythropoietin (EPO) in several cancers is associated with decreased survival due to cancer progression. Due to the major importance of telomerase in cancer biology we hypothesized that some of these effects may be mediated through EPO effect on telomerase. For this aim we explored the possible effects of EPO on telomerase regulation, cell migration and chemosensitivity in non-erythroid malignant and non-malignant cells. Cell proliferation, telomerase activity (TA) and cell migration increased in response to EPO. EPO had no effect on cancer cells sensitivity to cisplatinum and on the cell cycle status. The inhibition of telomerase modestly repressed the proliferative effect of EPO. Telomere shortening caused by long term inhibition of the enzyme abolished the effect of EPO, suggesting that EPO effects on cancer cells are related to telomere dynamics. TA was correlated with the levels of Epo-R. The increase in TA was mediated post-translationally through the Lyn-Src and not the canonical JAK2 pathway.

  11. HIV-1 gp120 impairs the differentiation and survival of cord blood CD34+ HPCs induced to the erythroid lineage.

    PubMed

    Morini, Silvia; Musumeci, Giuseppina; Bon, Isabella; Miserocchi, Anna; Alviano, Francesco; Longo, Serena; Bertoldi, Alessia; Velati, Claudio V; Gibellini, Davide; Re, Maria Carla

    2016-01-01

    Anemia is the most common hematological abnormality in human immunodeficiency virus (HIV)-infected patients. Besides chronic disease, opportunistic infections, nutritional deficiencies and antiretroviral drug toxicity, the direct role of HIV in the development of anemia has not yet been fully investigated. To explore the HIV-related mechanisms involved in the genesis of anemia, we used two experimental designs. In the first, HPCs purified from cord blood were challenged with HIV-1IIIb or recombinant gp120 (rgp120) and then committed to erythrocyte differentiation (EPO-post-treated HPCs). In the second, HPCs were first committed to differentiate towards the erythroid lineage and only afterwards challenged with HIV-1IIIb or rgp120 (EPO-pre-treated HPCs). Our results showed that HPCs and EPO-induced HPCs were not susceptible to HIV-1 infection. In addition, the two experimental designs (EPO post or pre-treated HPCs) independently showed that HIV-1IIIb or rgp120 were able to induce the impairment of survival, proliferation, and differentiation albeit differing in kinetics and extent. Interestingly, the gp120 interaction with CD4 and CXCR4 played a pivotal role in the impairment of erythrocyte differentiation by inducing TGF-b1 expression. These observations reveal an important additional mechanism involved in the genesis of anemia suggesting a complex competition between EPO-positive regulation and HIV-negative priming regarding erythrocyte survival, proliferation and maturation. PMID:26922982

  12. Structure of the Membrane Proximal Oxioreductase Domain of Human Steap3, the Dominant Ferrireductase of the Erythroid Transferrin Cycle

    SciTech Connect

    Sendamarai, A.K.; Ohgami, R.S.; Fleming, M.D.; Lawrence, C.M.

    2009-05-27

    The daily production of 200 billion erythrocytes requires 20 mg of iron, accounting for nearly 80% of the iron demand in humans. Thus, erythroid precursor cells possess an efficient mechanism for iron uptake in which iron loaded transferrin (Tf) binds to the transferrin receptor (TfR) at the cell surface. The Tf:TfR complex then enters the endosome via receptor-mediated endocytosis. Upon endosomal acidification, iron is released from Tf, reduced to Fe{sup 2+} by Steap3, and transported across the endosomal membrane by divalent metal iron transporter 1. Steap3, the major ferrireductase in erythrocyte endosomes, is a member of a unique family of reductases. Steap3 is comprised of an N-terminal cytosolic oxidoreductase domain and a C-terminal heme-containing transmembrane domain. Cytosolic NADPH and a flavin are predicted cofactors, but the NADPH/flavin binding domain differs significantly from those in other eukaryotic reductases. Instead, Steap3 shows remarkable, although limited homology to FNO, an archaeal oxidoreductase. We have determined the crystal structure of the human Steap3 oxidoreductase domain in the absence and presence of NADPH. The structure reveals an FNO-like domain with an unexpected dimer interface and substrate binding sites that are well positioned to direct electron transfer from the cytosol to a heme moiety predicted to be fixed within the transmembrane domain. Here, we discuss possible gating mechanisms for electron transfer across the endosomal membrane.

  13. Nuclear Factor Erythroid 2-Related Factor 2 Deficiency Results in Amplification of the Liver Fat-Lowering Effect of Estrogen.

    PubMed

    Rui, Wenjuan; Zou, Yuhong; Lee, Joonyong; Nambiar, Shashank Manohar; Lin, Jingmei; Zhang, Linjie; Yang, Yan; Dai, Guoli

    2016-07-01

    Transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) regulates multiple biologic processes, including hepatic lipid metabolism. Estrogen exerts actions affecting energy homeostasis, including a liver fat-lowering effect. Increasing evidence indicates the crosstalk between these two molecules. The aim of this study was to evaluate whether Nrf2 modulates estrogen signaling in hepatic lipid metabolism. Nonalcoholic fatty liver disease (NAFLD) was induced in wild-type and Nrf2-null mice fed a high-fat diet and the liver fat-lowering effect of exogenous estrogen was subsequently assessed. We found that exogenous estrogen eliminated 49% and 90% of hepatic triglycerides in wild-type and Nrf2-null mice with NAFLD, respectively. This observation demonstrates that Nrf2 signaling is antagonistic to estrogen signaling in hepatic fat metabolism; thus, Nrf2 absence results in striking amplification of the liver fat-lowering effect of estrogen. In addition, we found the association of trefoil factor 3 and fatty acid binding protein 5 with the liver fat-lowering effect of estrogen. In summary, we identified Nrf2 as a novel and potent inhibitor of estrogen signaling in hepatic lipid metabolism. Our finding may provide a potential strategy to treat NAFLD by dually targeting Nrf2 and estrogen signaling. PMID:27189962

  14. Structural characterization of a noncovalent complex between ubiquitin and the transactivation domain of the erythroid-specific factor EKLF.

    PubMed

    Raiola, Luca; Lussier-Price, Mathieu; Gagnon, David; Lafrance-Vanasse, Julien; Mascle, Xavier; Arseneault, Genevieve; Legault, Pascale; Archambault, Jacques; Omichinski, James G

    2013-11-01

    Like other acidic transactivation domains (TAD), the minimal TAD from the erythroid-specific transcription factor EKLF (EKLFTAD) has been shown to contribute both to its transcriptional activity as well as to its ubiquitin(UBI)-mediated degradation. In this article, we examine the activation-degradation role of the acidic TAD of EKLF and demonstrate that the first 40 residues (EKLFTAD1) within this region form a noncovalent interaction with UBI. Nuclear magnetic resonance (NMR) structural studies of an EKLFTAD1-UBI complex show that EKLFTAD1 adopts a 14-residue α helix that forms the recognition interface with UBI in a similar manner as the UBI-interacting helix of Rabex5. We also identify a similar interaction between UBI and the activation-degradation region of SREBP1a, but not with the activation-degradation regions of p53, GAL4, and VP16. These results suggest that select activation-degradation regions like the ones found in EKLF and SREBP1a function in part through their ability to form noncovalent interactions with UBI. PMID:24139988

  15. Human and Murine Hematopoietic Stem Cell Aging Is Associated with Functional Impairments and Intrinsic Megakaryocytic/Erythroid Bias

    PubMed Central

    Rundberg Nilsson, Alexandra; Soneji, Shamit; Adolfsson, Sofia; Bryder, David; Pronk, Cornelis Jan

    2016-01-01

    Aging within the human hematopoietic system associates with various deficiencies and disease states, including anemia, myeloid neoplasms and reduced adaptive immune responses. Similar phenotypes are observed in mice and have been linked to alterations arising at the hematopoietic stem cell (HSC) level. Such an association is, however, less established in human hematopoiesis and prompted us here to detail characteristics of the most primitive human hematopoietic compartments throughout ontogeny. In addition, we also attempted to interrogate similarities between aging human and murine hematopoiesis. Coupled to the transition from human cord blood (CB) to young and aged bone marrow (BM), we observed a gradual increase in frequency of candidate HSCs. This was accompanied by functional impairments, including decreased lymphoid output and reduced proliferative potential. Downstream of human HSCs, we observed decreasing levels of common lymphoid progenitors (CLPs), and increasing frequencies of megakaryocyte/erythrocyte progenitors (MEPs) with age, which could be linked to changes in lineage-affiliated gene expression patterns in aged human HSCs. These findings were paralleled in mice. Therefore, our data support the notion that age-related changes also in human hematopoiesis involve the HSC pool, with a prominent skewing towards the megakaryocytic/erythroid lineages, and suggests conserved mechanisms underlying aging of the blood cell system. PMID:27368054

  16. Neuroprotective effects of salidroside on focal cerebral ischemia/reperfusion injury involve the nuclear erythroid 2-related factor 2 pathway

    PubMed Central

    Han, Jing; Xiao, Qing; Lin, Yan-hua; Zheng, Zhen-zhu; He, Zhao-dong; Hu, Juan; Chen, Li-dian

    2015-01-01

    Salidroside, the main active ingredient extracted from Rhodiola crenulata, has been shown to be neuroprotective in ischemic cerebral injury, but the underlying mechanism for this neuroprotection is poorly understood. In the current study, the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway was investigated in a rat model of middle cerebral artery occlusion. Salidroside (30 mg/kg) reduced infarct size, improved neurological function and histological changes, increased activity of superoxide dismutase and glutathione-S-transferase, and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion. Furthermore, salidroside apparently increased Nrf2 and heme oxygenase-1 expression. These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved. The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke. PMID:26889188

  17. Structure of the membrane proximal oxidoreductase domain of human Steap3, the dominant ferrireductase of the erythroid transferrin cycle

    PubMed Central

    Sendamarai, Anoop K.; Ohgami, Robert S.; Fleming, Mark D.; Lawrence, C. Martin

    2008-01-01

    The daily production of 200 billion erythrocytes requires 20 mg of iron, accounting for nearly 80% of the iron demand in humans. Thus, erythroid precursor cells possess an efficient mechanism for iron uptake in which iron loaded transferrin (Tf) binds to the transferrin receptor (TfR) at the cell surface. The Tf:TfR complex then enters the endosome via receptor-mediated endocytosis. Upon endosomal acidification, iron is released from Tf, reduced to Fe2+ by Steap3, and transported across the endosomal membrane by divalent metal iron transporter 1. Steap3, the major ferrireductase in erythrocyte endosomes, is a member of a unique family of reductases. Steap3 is comprised of an N-terminal cytosolic oxidoreductase domain and a C-terminal heme-containing transmembrane domain. Cytosolic NADPH and a flavin are predicted cofactors, but the NADPH/flavin binding domain differs significantly from those in other eukaryotic reductases. Instead, Steap3 shows remarkable, although limited homology to FNO, an archaeal oxidoreductase. We have determined the crystal structure of the human Steap3 oxidoreductase domain in the absence and presence of NADPH. The structure reveals an FNO-like domain with an unexpected dimer interface and substrate binding sites that are well positioned to direct electron transfer from the cytosol to a heme moiety predicted to be fixed within the transmembrane domain. Here, we discuss possible gating mechanisms for electron transfer across the endosomal membrane. PMID:18495927

  18. Correction of murine β-thalassemia after minimal lentiviral gene transfer and homeostatic in vivo erythroid expansion

    PubMed Central

    Negre, Olivier; Fusil, Floriane; Colomb, Charlotte; Roth, Shoshannah; Gillet-Legrand, Beatrix; Henri, Annie; Beuzard, Yves; Bushman, Frederic; Leboulch, Philippe

    2011-01-01

    A challenge for gene therapy of genetic diseases is to maintain corrected cell populations in subjects undergoing transplantation in cases in which the corrected cells do not have intrinsic selective advantage over nontransduced cells. For inherited hematopoietic disorders, limitations include inefficient transduction of stem cell pools, the requirement for toxic myelosuppression, and a lack of optimal methods for cell selection after transduction. Here, we have designed a lentiviral vector that encodes human β-globin and a truncated erythropoietin receptor, both under erythroid-specific transcriptional control. This truncated receptor confers enhanced sensitivity to erythropoietin and a benign course in human carriers. Transplantation of marrow transduced with the vector into syngenic thalassemic mice, which have elevated plasma erythropoietin levels, resulted in long-term correction of the disease even at low ratios of transduced/untransduced cells. Amplification of the red over the white blood cell lineages was self-controlled and averaged ∼ 100-fold instead of ∼ 5-fold for β-globin expression alone. There was no detectable amplification of white blood cells or alteration of hematopoietic homeostasis. Notwithstanding legitimate safety concerns in the context of randomly integrating vectors, this approach may prove especially valuable in combination with targeted integration or in situ homologous recombination/repair and may lower the required level of pretransplantation myelosuppression. PMID:21436071

  19. Professional Development Leading to Sustained Change

    ERIC Educational Resources Information Center

    Stickney, Catherine Alaimo

    2012-01-01

    Determining effective change that leads to sustainable improved student achievement remains an elusive goal for most educational communities. This research addresses the question of what factors of professional development promote sustained change within a school organization. The survey questions focus on the formation of professional learning…

  20. Our Vision for a Sustainable Wales

    ERIC Educational Resources Information Center

    Davidson, Jane

    2010-01-01

    The Welsh Assembly Government is committed to putting sustainable development at the heart of all it does. In May 2009, the Assembly launched its latest scheme, "One Wales: One Planet," which sets out a clear definition of sustainable development as enhancing the economic, social and environmental wellbeing of people and communities, achieving a…

  1. Fostering Organizational Sustainability through Dialogical Interaction

    ERIC Educational Resources Information Center

    Wals, Arjen E. J.; Schwarzin, Lisa

    2012-01-01

    Purpose: This paper aims to introduce and investigate dialogic interaction as a key element of achieving a transition towards sustainability in people, organizations and society as a whole. Furthermore "sustainability competence" as a potential outcome of such interaction is to be introduced, referring to the capacities and qualities that people,…

  2. Shifting Sights: The Cultural Challenge of Sustainability

    ERIC Educational Resources Information Center

    Thaman, Konai H.

    2002-01-01

    This article focuses on the need for universities as teaching and research organisations, to recognise and act upon a more culturally inclusive interpretation of "sustainable development" and "sustainability". It argues for the valuing of indigenous worldviews as a means of achieving a more holistic and interdisciplinary way of thinking about the…

  3. Sustainable water management practices and remote sensing.

    EPA Science Inventory

    The United States Environmental Protection Agency’s charge to protect human health and the environment requires a long-term commitment to creating sustainable solutions to environmental problems. The most direct way to ensure that management practices are achieving sustainability...

  4. Online PBL: A Route to Sustainability Education?

    ERIC Educational Resources Information Center

    Tomkinson, Bland; Hutt, Ian

    2012-01-01

    Purpose: The purpose of this paper is to investigate online problem-based learning (PBL) as a route to achieving sustainability education using sponsored projects. Design/methodology/approach: The Royal Academy of Engineering sponsored project at Manchester; to foster education in sustainability through inter-disciplinary problem-based approaches,…

  5. Dynamics of α-globin locus chromatin structure and gene expression during erythroid differentiation of human CD34+ cells in culture

    PubMed Central

    Mahajan, Milind C; Karmakar, Subhradip; Krause, Diane; Weissman, Sherman M

    2009-01-01

    Objective The aim of the present study has been to establish serum free culture conditions for the ex vivo expansion and differentiation of human CD34+ cells into erythroid lineage and to study the chromatin structure, gene expression and transcription factor recruitment at the α–globin locus in the developing erythron. Methods A basal IMDM cell culture medium with 1% bovine serum albumin as a serum replacement and a combination of cytokines and growth factors was used for the expansion and differentiation of the CD34+ cells. Expression patterns of the alpha and beta like genes at various stages of erythropoiesis was studied by Reverse transcriptase (RT)-qPCR analysis, profile of key erythroid transcription factors was investigated by western blotting, and the chromatin structure and transcription factor recruitment at the alpha globin locus was investigated by ChIP-qPCR analysis. Results Human CD34+ cells in the serum free medium undergo near synchronous erythroid differentiation to yield large amount of cells at different differentiation stages. We observe distinct patterns of the histone modifications and transcription factor binding at the α-globin locus during erythroid differentiation of CD34+ cells. NF-E2 was present at upstream activator sites even before addition of erythropoietin (Epo), while bound GATA-1 was only detectable after Epo treatment. After seven days of erythropoietin treatment, H3K4Me2 modification uniformly increases throughout the α–globin locus. Acetylation at H3K9 and binding of Pol II, NF-E2 and GATA-1 were restricted to certain HS sites of the enhancer and theta gene, and were conspicuously low at the α-like globin promoters. Rearrangement of the insulator binding factor CTCF took place at and around the α-globin locus as CD34+ cells differentiated into erythroid pathway. Conclusion Our results indicate that remodeling of the upstream elements may be the primary event in activation of α–globin gene expression. Activation of

  6. Materials for Sustainable Energy

    NASA Astrophysics Data System (ADS)

    Crabtree, George

    2009-03-01

    The global dependence on fossil fuels for energy is among the greatest challenges facing our economic, social and political future. The uncertainty in the cost and supply of oil threatens the global economy and energy security, the pollution of fossil combustion threatens human health, and the emission of greenhouse gases threatens global climate. Meeting the demand for double the current global energy use in the next 50 years without damaging our economy, security, environment or climate requires finding alternative sources of energy that are clean, abundant, accessible and sustainable. The transition to greater sustainability involves tapping unused energy flows such as sunlight and wind, producing electricity without carbon emissions from clean coal and high efficiency nuclear power plants, and using energy more efficiently in solid-state lighting, fuel cells and transportation based on plug-in hybrid and electric cars. Achieving these goals requires creating materials of increasing complexity and functionality to control the transformation of energy between light, electrons and chemical bonds. Challenges and opportunities for developing the complex materials and controlling the chemical changes that enable greater sustainability will be presented.

  7. Day one sustainability

    NASA Astrophysics Data System (ADS)

    Orr, John; Ibell, Timothy; Evernden, Mark; Darby, Antony

    2015-05-01

    Emissions reductions targets for the UK set out in the Climate Change Act for the period to 2050 will only be achieved with significant changes to the built environment, which is currently estimated to account for 50% of the UK's carbon emissions. The socio-technological nature of Civil Engineering means that this field is uniquely placed to lead the UK through such adaptations. This paper discusses the importance of interdisciplinary teaching to produce multi-faceted team approaches to sustainable design solutions. Methods for measuring success in education are often not fit for purpose, producing good students but poor engineers. Real-world failures to apply sustainable design present a serious, difficult to detect, and ultimately economically negative situation. Techniques to replace summative examinations are presented and discussed, with the aim of enhancing core technical skills alongside those required for sustainable design. Finally, the role of our future engineers in policy-making is discussed. In addition to carbon, the provision of water and food will heavily influence the work of civil engineers in the coming decades. Leadership from civil engineers with the technical knowledge and social awareness to tackle these issues will be required. This provides both opportunities and challenges for engineering education in the UK.

  8. Sustainability Science Needs Sustainable Data!

    NASA Astrophysics Data System (ADS)

    Downs, R. R.; Chen, R. S.

    2013-12-01

    Sustainability science (SS) is an 'emerging field of research dealing with the interactions between natural and social systems, and with how those interactions affect the challenge of sustainability: meeting the needs of present and future generations while substantially reducing poverty and conserving the planet's life support systems' (Kates, 2011; Clark, 2007). Bettencourt & Kaur (2011) identified more than 20,000 scientific papers published on SS topics since the 1980s with more than 35,000 distinct authors. They estimated that the field is currently growing exponentially, with the number of authors doubling approximately every 8 years. These scholars are undoubtedly using and generating a vast quantity and variety of data and information for both SS research and applications. Unfortunately we know little about what data the SS community is actually using, and whether or not the data that SS scholars generate are being preserved for future use. Moreover, since much SS research is conducted by cross-disciplinary, multi-institutional teams, often scattered around the world, there could well be increased risks of data loss, reduced data quality, inadequate documentation, and poor long-term access and usability. Capabilities and processes therefore need to be established today to support continual, reliable, and efficient preservation of and access to SS data in the future, especially so that they can be reused in conjunction with future data and for new studies not conceived in the original data collection activities. Today's long-term data stewardship challenges include establishing sustainable data governance to facilitate continuing management, selecting data to ensure that limited resources are focused on high priority SS data holdings, securing sufficient rights to allow unforeseen uses, and preparing data to enable use by future communities whose specific research and information needs are not yet known. Adopting sustainable models for archival

  9. Sustainable systems as organisms?

    PubMed

    Ho, Mae-Wan; Ulanowicz, Robert

    2005-10-01

    Schrödinger [Schrödinger, E., 1944. What is Life? Cambridge University Press, Cambridge] marvelled at how the organism is able to use metabolic energy to maintain and even increase its organisation, which could not be understood in terms of classical statistical thermodynamics. Ho [Ho, M.W., 1993. The Rainbow and the Worm, The Physics of Organisms, World Scientific, Singapore; Ho, M.W., 1998a. The Rainbow and the Worm, The Physics of Organisms, 2nd (enlarged) ed., reprinted 1999, 2001, 2003 (available online from ISIS website www.i-sis.org.uk)] outlined a novel "thermodynamics of organised complexity" based on a nested dynamical structure that enables the organism to maintain its organisation and simultaneously achieve non-equilibrium and equilibrium energy transfer at maximum efficiency. This thermodynamic model of the organism is reminiscent of the dynamical structure of steady state ecosystems identified by Ulanowicz [Ulanowicz, R.E., 1983. Identifying the structure of cycling in ecosystems. Math. Biosci. 65, 210-237; Ulanowicz, R.E., 2003. Some steps towards a central theory of ecosystem dynamics. Comput. Biol. Chem. 27, 523-530]. The healthy organism excels in maintaining its organisation and keeping away from thermodynamic equilibrium--death by another name--and in reproducing and providing for future generations. In those respects, it is the ideal sustainable system. We propose therefore to explore the common features between organisms and ecosystems, to see how far we can analyse sustainable systems in agriculture, ecology and economics as organisms, and to extract indicators of the system's health or sustainability. We find that looking at sustainable systems as organisms provides fresh insights on sustainability, and offers diagnostic criteria for sustainability that reflect the system's health. In the case of ecosystems, those diagnostic criteria of health translate into properties such as biodiversity and productivity, the richness of cycles, the

  10. Farming with Grass: Achieving Sustainable Mixed Agricultural Landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Grassla...

  11. Foreword to farming with grass: Achieving sustainable mixed agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Farming with Grass conference was developed to bring together diverse stakeholders in grassland environments to (a) help assess the current condition of agriculture, (b) consider alternative production scenarios for grassland agricultural ecosystems, (c) identify key issues hindering the develop...

  12. Sustainable Scientists

    SciTech Connect

    Mills, Evan

    2008-12-31

    Scientists are front and center in quantifying and solving environmental problems. Yet, as a spate of recent news articles in scientific journals point out, much can be done to enhance sustainability within the scientific enterprise itself, particularly by trimming the energy use associated with research facilities and the equipment therein (i,ii,iii, iv). Sponsors of research unwittingly spend on the order of $10 billion each year on energy in the U.S. alone, and the underlying inefficiencies drain funds from the research enterprise while causing 80 MT CO2-equivalent greenhouse-gas emissions (see Box). These are significant sums considering the opportunity costs in terms of the amount of additional research that could be funded and emissions that could be reduced if the underlying energy was used more efficiently. By following commercially proven best practices in facility design and operation, scientists--and the sponsors of science--can cost-effectively halve these costs, while doing their part to put society on alow-carbon diet.

  13. Electrification will enable sustained prosperity

    SciTech Connect

    Linden, H.R.

    1996-10-01

    The author addresses this topic from the perspective of a technological optimist who believes by 2100 the global energy system will have achieved sustainability or, at least, closely approached it. What will drive this evolution to resource and environmental sustainability is not depletion of economically recoverable fossil fuels or the current anxiety over anthropogenic climate change. Instead, it will be an avalanche of new cost-effective and environmentally benign energy supply, transport, storage and end-use technologies that will change the global energy system even more dramatically than the technological advances of the past 100 years.

  14. Crystal Structure of the Nonerythroid [alpha]-Spectrin Tetramerization Site Reveals Differences between Erythroid and Nonerythroid Spectrin Tetramer Formation

    SciTech Connect

    Mehboob, Shahila; Song, Yuanli; Witek, Marta; Long, Fei; Santarsiero, Bernard D.; Johnson, Michael E.; Fung, Leslie W.-M.

    2010-06-21

    We have solved the crystal structure of a segment of nonerythroid {alpha}-spectrin ({alpha}II) consisting of the first 147 residues to a resolution of 2.3 {angstrom}. We find that the structure of this segment is generally similar to a corresponding segment from erythroid {alpha}-spectrin ({alpha}I) but exhibits unique differences with functional significance. Specific features include the following: (i) an irregular and frayed first helix (Helix C{prime}); (ii) a helical conformation in the junction region connecting Helix C{prime} with the first structural domain (D1); (iii) a long A1B1 loop in D1; and (iv) specific inter-helix hydrogen bonds/salt bridges that stabilize D1. Our findings suggest that the hydrogen bond networks contribute to structural domain stability, and thus rigidity, in {alpha}II, and the lack of such hydrogen bond networks in {alpha}I leads to flexibility in {alpha}I. We have previously shown the junction region connecting Helix C{prime} to D1 to be unstructured in {alpha}I (Park, S., Caffrey, M. S., Johnson, M. E., and Fung, L. W. (2003) J. Biol. Chem. 278, 21837-21844) and now find it to be helical in {alpha}II, an important difference for {alpha}-spectrin association with {beta}-spectrin in forming tetramers. Homology modeling and molecular dynamics simulation studies of the structure of the tetramerization site, a triple helical bundle of partial domain helices, show that mutations in {alpha}-spectrin will affect Helix C{prime} structural flexibility and/or the junction region conformation and may alter the equilibrium between spectrin dimers and tetramers in cells. Mutations leading to reduced levels of functional tetramers in cells may potentially lead to abnormal neuronal functions.

  15. Protective role of nuclear factor erythroid 2-related factor 2 in the hemorrhagic shock-induced inflammatory response

    PubMed Central

    ZHAO, HAIGE; HAO, SIJING; XU, HONGFEI; MA, LIANG; ZHANG, ZHENG; NI, YIMING; YU, LUYANG

    2016-01-01

    Hemorrhagic shock (HS) following trauma or major surgery significantly contributes to mortality. However, the mechanisms through which HS activates the inflammatory response are not yet fully understood. Nuclear factor-erythroid 2 (NF-E2) p45-related factor-2 (Nrf2), a bZIP transcription factor, is a master regulator of robust cytoprotective defenses. The present study investigated the role of Nrf2 in the pathophysiology of HS. Nrf2 expression in peripheral leukocytes obtained from patients with surgery-associated hemorrhage subjected to resuscitation treatment (termed HS patients) or healthy donors was examined by RT-qPCR. A marked increase in Nrf2 expression was detected in the leukocytes obtained from the HS patients, which indicates a correlation between Nrf2 expression and the development of HS. Wild-type (WT; Nrf2+/+) and Nrf2-deficient [Nrf2−/− or Nrf2-knockout (KO)] mice were subjected to surgery to induce HS. Systemic inflammation was significantly elevated in the Nrf2-KO mice compared with the WT mice following HS, as assessed by an increase in serum cytokine levels [interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL-1β], as well as high-mobility group box 1 protein (HMGB1) expression. The Nrf2-KO mice exhibited more severe lung and liver injury following HS as evidenced by increased tissue damage, increased myeloperoxidase (MPO) activity and the increased production of pro-inflammatory cytokines. Additionally, Nrf2 deficiency augmented cytokine production induced by the exposure of peritoneal mouse macrophages to lipopolysaccha-ride (LPS) following HS. Taken together, these results suggest that Nrf2 is a critical host factor which limits immune dysregulation and organ injury following HS. PMID:26935388

  16. Asn-150 of Murine Erythroid 5-Aminolevulinate Synthase Modulates the Catalytic Balance between the Rates of the Reversible Reaction.

    PubMed

    Stojanovski, Bosko M; Ferreira, Gloria C

    2015-12-25

    5-Aminolevulinate synthase (ALAS) catalyzes the first step in mammalian heme biosynthesis, the pyridoxal 5'-phosphate (PLP)-dependent and reversible reaction between glycine and succinyl-CoA to generate CoA, CO2, and 5-aminolevulinate (ALA). Apart from coordinating the positioning of succinyl-CoA, Rhodobacter capsulatus ALAS Asn-85 has a proposed role in regulating the opening of an active site channel. Here, we constructed a library of murine erythroid ALAS variants with substitutions at the position occupied by the analogous bacterial asparagine, screened for ALAS function, and characterized the catalytic properties of the N150H and N150F variants. Quinonoid intermediate formation occurred with a significantly reduced rate for either the N150H- or N150F-catalyzed condensation of glycine with succinyl-CoA during a single turnover. The introduced mutations caused modifications in the ALAS active site such that the resulting variants tipped the balance between the forward- and reverse-catalyzed reactions. Although wild-type ALAS catalyzes the conversion of ALA into the quinonoid intermediate at a rate 6.3-fold slower than the formation of the same quinonoid intermediate from glycine and succinyl-CoA, the N150F variant catalyzes the forward reaction at a mere 1.2-fold faster rate than that of the reverse reaction, and the N150H variant reverses the rate values with a 1.7-fold faster rate for the reverse reaction than that for the forward reaction. We conclude that the evolutionary selection of Asn-150 was significant for optimizing the forward enzymatic reaction at the expense of the reverse, thus ensuring that ALA is predominantly available for heme biosynthesis. PMID:26511319

  17. Protective role of nuclear factor erythroid 2-related factor 2 in the hemorrhagic shock-induced inflammatory response.

    PubMed

    Zhao, Haige; Hao, Sijing; Xu, Hongfei; Ma, Liang; Zhang, Zheng; Ni, Yiming; Yu, Luyang

    2016-04-01

    Hemorrhagic shock (HS) following trauma or major surgery significantly contributes to mortality. However, the mechanisms through which HS activates the inflammatory response are not yet fully understood. Nuclear factor-erythroid 2 (NF-E2) p45-related factor-2 (Nrf2), a bZIP transcription factor, is a master regulator of robust cytoprotective defenses. The present study investigated the role of Nrf2 in the pathophysiology of HS. Nrf2 expression in peripheral leukocytes obtained from patients with surgery-associated hemorrhage subjected to resuscitation treatment (termed HS patients) or healthy donors was examined by RT-qPCR. A marked increase in Nrf2 expression was detected in the leukocytes obtained from the HS patients, which indicates a correlation between Nrf2 expression and the development of HS. Wild-type (WT; Nrf2+/+) and Nrf2-deficient [Nrf2-/- or Nrf2‑knockout (KO)] mice were subjected to surgery to induce HS. Systemic inflammation was significantly elevated in the Nrf2-KO mice compared with the WT mice following HS, as assessed by an increase in serum cytokine levels [interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL-1β], as well as high-mobility group box 1 protein (HMGB1) expression. The Nrf2-KO mice exhibited more severe lung and liver injury following HS as evidenced by increased tissue damage, increased myeloperoxidase (MPO) activity and the increased production of pro-inflammatory cytokines. Additionally, Nrf2 deficiency augmented cytokine production induced by the exposure of peritoneal mouse macrophages to lipopolysaccharide (LPS) following HS. Taken together, these results suggest that Nrf2 is a critical host factor which limits immune dysregulation and organ injury following HS. PMID:26935388

  18. Biochemical measurements on single erythroid progenitor cells shed light on the combinatorial regulation of red blood cell production.

    PubMed

    Wang, Weijia; Akbarian, Vahe; Audet, Julie

    2013-02-01

    Adult bone marrow (BM) erythrocyte colony-forming units (CFU-Es) are important cellular targets for the treatment of anemia and also for the manufacture of red blood cells (RBCs) ex vivo. We obtained quantitative biochemical measurements from single and small numbers of CFU-Es by isolating and analyzing c-Kit(+)CD71(high)Ter119(-) cells from adult mouse BM and this allowed us to identify two mechanisms that can be manipulated to increase RBC production. As expected, maximum RBC output was obtained when CFU-Es were stimulated with a combination of Stem Cell Factor (SCF) and Erythropoietin (EPO) mainly because SCF supports a transient CFU-E expansion and EPO promotes the survival and terminal differentiation of erythroid progenitors. However, we found that one of the main factors limiting the output in RBCs was that EPO induces a downregulation of c-Kit expression which limits the transient expansion of CFU-Es. In the presence of SCF, the EPO-mediated downregulation of c-Kit on CFU-Es is delayed but still significant. Moreover, treatment of CFU-Es with 1-Naphthyl PP1 could partially inhibit the downregulation of c-Kit induced by EPO, suggesting that this process is dependent on a Src family kinase, v-Src and/or c-Fyn. We also found that CFU-E survival and proliferation was dependent on the level of time-integrated extracellular-regulated kinase (ERK) activation in these cells, all of which could be significantly increased when SCF and EPO were combined with mouse fetal liver-derived factors. Taken together, these results suggest two novel molecular strategies to increase RBC production and regeneration. PMID:23168618

  19. Oxidative Damage and Nuclear Factor Erythroid 2-Related Factor 2 Protein Expression in Normal Skin and Keloid Tissue

    PubMed Central

    Lee, Yoon Jin; Kwon, Sun Bum; Kim, Chul Han; Cho, Hyun Deuk; Nam, Hae Seon; Lee, Sang Han; Lee, Mi Woo; Nam, Doo Hyun; Choi, Chang Yong

    2015-01-01

    Background Reactive oxygen species (ROS) play an important role in the induction of apoptosis under pathological conditions. Recently, a significant increase in ROS production and disrupted apoptosis mechanisms in keloids have been reported. Nuclear factor erythroid 2-related factor 2 (Nrf2) represents one of the most important cellular defense mechanisms against oxidative stress and is implicated in the regulation of apoptosis. Recently, it has been reported that Nrf2 upregulates Bcl-2, an anti-apoptotic protein. Objective To compare Nrf2 protein expression in normal skin tissues to keloid tissues. Methods ROS generation in keloid tissues was evaluated with OxyBlot analysis. Western blotting and/or immunohistochemical staining approaches were used to study expression of Nrf2 or Bcl-2 in keloid and normal skin tissues. Cellular fractionation was performed to examine subcellular distribution of Nrf2. Transfection of fibroblasts with Nrf2-specific small interfering RNA (siRNA) was conducted to understand the relationship between Nrf2 expression and apoptosis induction. Results Protein oxidation, a marker of oxidative stress, is increased in keloid tissues. Western blot analysis clearly showed that Nrf2 and Bcl-2 are downregulated in keloid tissues. Immunohistochemical staining of Nrf2 confirmed the results of the western blot analysis. Transfection of fibroblasts with the Nrf2-specific siRNA results in increased apoptosis and decreased cell viability. Conclusion Collectively, our data indicate that Nrf2 expression is downregulated in keloid tissues, and that Nrf2 is involved in the development of apoptosis in Nrf2 siRNA-transfected fibroblasts. We propose that a defective antioxidant system and apoptotic dysregulation may participate in keloid pathogenesis. PMID:26512164

  20. The Nuclear Factor (Erythroid-derived 2)-like 2 and Proteasome Maturation Protein Axis Mediate Bortezomib Resistance in Multiple Myeloma.

    PubMed

    Li, Bingzong; Fu, Jinxiang; Chen, Ping; Ge, Xueping; Li, Yali; Kuiatse, Isere; Wang, Hua; Wang, Huihan; Zhang, Xingding; Orlowski, Robert Z

    2015-12-11

    Resistance to the proteasome inhibitor bortezomib is an emerging clinical problem whose mechanisms have not been fully elucidated. We considered the possibility that this could be associated with enhanced proteasome activity in part through the action of the proteasome maturation protein (POMP). Bortezomib-resistant myeloma models were used to examine the correlation between POMP expression and bortezomib sensitivity. POMP expression was then modulated using genetic and pharmacologic approaches to determine the effects on proteasome inhibitor sensitivity in cell lines and in vivo models. Resistant cell lines were found to overexpress POMP, and while its suppression in cell lines enhanced bortezomib sensitivity, POMP overexpression in drug-naive cells conferred resistance. Overexpression of POMP was associated with increased levels of nuclear factor (erythroid-derived 2)-like (NRF2), and NRF2 was found to bind to and activate the POMP promoter. Knockdown of NRF2 in bortezomib-resistant cells reduced POMP levels and proteasome activity, whereas its overexpression in drug-naive cells increased POMP and proteasome activity. The NRF2 inhibitor all-trans-retinoic acid reduced cellular NRF2 levels and increased the anti-proliferative and pro-apoptotic activities of bortezomib in resistant cells, while decreasing proteasome capacity. Finally, the combination of all-trans-retinoic acid with bortezomib showed enhanced activity against primary patient samples and in a murine model of bortezomib-resistant myeloma. Taken together, these studies validate a role for the NRF2/POMP axis in bortezomib resistance and identify NRF2 and POMP as potentially attractive targets for chemosensitization to this proteasome inhibitor. PMID:26483548

  1. Sustainable Campus: Engaging the Community in Sustainability

    ERIC Educational Resources Information Center

    Too, Linda; Bajracharya, Bhishna

    2015-01-01

    Purpose: The purpose of this paper is to identify the major factors necessary for engaging university campus community in sustainability. While general awareness in sustainability issues has improved in recent years through mass media coverage, this knowledge is not always translated into actual sustainable practice. Studies have indicated that…

  2. siDNMT1 Increases γ-globin Expression in Chemical-Inducer-of-Dimerization (CID)-Dependent Mouse βYAC Bone Marrow Cells and in Baboon Erythroid Progenitor Cell Cultures

    PubMed Central

    Banzon, Virryan; Ibanez, Vinzon; Vaitkus, Kestis; Ruiz, Maria Armila; Peterson, Kenneth; DeSimone, Joseph; Lavelle, Donald

    2014-01-01

    1) Objective These studies were performed to test the hypothesis that DNMT1 is required for maintenance of DNA methylation and repression of the γ-globin gene in adult stage erythroid cells. 2) Methods DNMT1 levels were reduced by nucleofection of siRNA targeting DNMT1 in chemical-inducer-of-dimerization (CID)-dependent multipotential mouse bone marrow (BM) cells containing the human β-globin gene locus in the context of a yeast artificial chromosome (βYAC) and in primary cultures of erythroid progenitor cells derived from CD34+ baboon BM cells. The effect of reduced DNMT1 levels on globin gene expression was measured by real time PCR and the effect on globin chain synthesis in primary erythroid progenitor cell cultures was determined by biosynthetic radiolabelling of globin chains followed by HPLC analysis. The effect on DNA methylation was determined by bisulfite sequence analysis. 3) Results Reduced DNMT1 levels in cells treated with siDNMT1 were associated with increased expression of γ-globin mRNA, an increased γ/γ+β chain ratio in cultured erythroid progenitors, and decreased DNA methylation of the γ-globin promoter. Similar effects were observed in cells treated with decitabine, a pharmacological inhibitor of DNA methyltransferase inhibitor. 4) Conclusion DNMT1 is required to maintain DNA methylation of the γ-globin gene promoters and repress γ-globin gene expression in adult-stage erythroid cells. PMID:20974210

  3. University Presidents' Conceptualizations of Sustainability in Higher Education

    ERIC Educational Resources Information Center

    Wright, Tarah

    2010-01-01

    Purpose: The purpose of this paper is to examine how a cohort of university presidents and vice-presidents in Canadian universities conceptualize sustainable development, sustainable universities, the role universities play in achieving a sustainable future, key issues facing the university, and the barriers to implementing sustainability…

  4. Compounds of the anthracycline family of antibiotics elevate human gamma-globin expression both in erythroid cultures and in a transgenic mouse model.

    PubMed

    Spyrou, Pandelis; Phylactides, Marios; Lederer, Carsten W; Kithreotis, Lucas; Kirri, Andriani; Christou, Soteroulla; Kkolou, Elena; Kanavakis, Emanuel; Anagnou, Nicholas P; Stamatoyannopoulos, George; Kleanthous, Marina

    2010-01-01

    We examined the effect of the anthracyclines aclarubicin, bleomycin, daunorubicin, doxorubicin and idarubicin on human gamma- and beta-globin promoter activity in an in vitro luciferase assay, ex vivo in erythroid cultures and in vivo in transgenic mice carrying the human gamma-globin gene. Effects in erythroid liquid cultures derived from healthy donors were assayed by evaluating HbF production with high performance liquid chromatography and by measuring mRNA levels of the globin genes and the proportion of erythroblasts containing HbF. Compounds testing positive in the in vitro and ex vivo assays were applied to erythroid cultures derived from thalassaemic patients. Doxorubicin, idarubicin and daunorubicin increased HbF production in cultures of both, healthy and thalassaemic donors. Daunorubicin induced HbF in thalassaemic cells ex vivo with the highest statistical significance and, importantly and in contrast to the clinical HbF inducer hydroxyurea, showed specific induction of gamma-globin without associated induction of alpha-globin. Daunorubicin was screened in transgenic mice carrying the human (A)gamma-globin gene, and it resulted in increased (A)gamma-globin mRNA levels. Our results indicate that anthracyclines are a promising group of compounds with the potential to provide lead substances for the synthesis of new agents with clinical applications as gamma-globin gene inducers. In parallel, future studies of the epigenetic effects of the five anthracyclines on the beta-globin locus will generate possible mechanistic leads on the regulation of the globin genes. PMID:19914848

  5. Impaired ferritin mRNA translation in primary erythroid progenitors: shift to iron-dependent regulation by the v-ErbA oncoprotein.

    PubMed

    Mikulits, W; Schranzhofer, M; Bauer, A; Dolznig, H; Lobmayr, L; Infante, A A; Beug, H; Müllner, E W

    1999-12-15

    In immortalized cells of the erythroid lineage, the iron-regulatory protein (IRP) has been suggested to coregulate biosynthesis of the iron storage protein ferritin and the erythroid delta-aminolevulinate synthase (eALAS), a key enzyme in heme production. Under iron scarcity, IRP binds to an iron-responsive element (IRE) located in ferritin and eALAS mRNA leaders, causing a block of translation. In contrast, IRP-IRE interaction is reduced under high iron conditions, allowing efficient translation. We show here that primary chicken erythroblasts (ebls) proliferating or differentiating in culture use a drastically different regulation of iron metabolism. Independently of iron administration, ferritin H (ferH) chain mRNA translation was massively decreased, whereas eALAS transcripts remained constitutively associated with polyribosomes, indicating efficient translation. Variations in iron supply had minor but significant effects on eALAS mRNA polysome recruitment but failed to modulate IRP-affinity to the ferH-IRE in vitro. However, leukemic ebls transformed by the v-ErbA/v-ErbB-expressing avian erythroblastosis virus showed an iron-dependent reduction of IRP mRNA-binding activity, resulting in mobilization of ferH mRNA into polysomes. Hence, we analyzed a panel of ebls overexpressing v-ErbA and/or v-ErbB oncoproteins as well as the respective normal cellular homologues (c-ErbA/TRalpha, c-ErbB/EGFR). It turned out that v-ErbA, a mutated class II nuclear hormone receptor that arrests erythroid differentiation, caused the change in ferH mRNA translation. Accordingly, inhibition of v-ErbA function in these leukemic ebls led to a switch from iron-responsive to iron-independent ferH expression. PMID:10590077

  6. A high concentration of triiodothyronine attenuates the stimulatory effect on hemin-induced erythroid differentiation of human erythroleukemia K562 cells.

    PubMed

    Shiraishi, Mieno; Yamamoto, Yoritsuna; Hirooka, Nobutaka; Obuchi, Yasuhiro; Tachibana, Shoichi; Makishima, Makoto; Tanaka, Yuji

    2015-01-01

    Although thyroid hormone is a known stimulator of erythropoietic differentiation, severe anemia is sometimes observed in patients with hyperthyroidism and this mechanism is not fully understood. The aim of this study was to investigate the effect of triiodothyronine (T3) on hemin-induced erythropoiesis. Human erythroleukemia K562 cells were used as an erythroid differentiation model. Cell differentiation was induced by hemin and the effect of pre-incubation with T3 (0.1 to 100 nM) was analyzed by measuring the benzidine-positive rate, hemoglobin content, CD71 expression (transferrin receptor), and mRNA expression for transcription factors related to erythropoiesis and thyroid hormone receptors (TRs). Hemin, a promoter of erythroid differentiation, increased the levels of mRNAs for TRα, TRβ, and retinoid X receptor α (RXRα), as well as those for nuclear factor-erythroid 2 (NFE2), GATA-binding protein 1 (GATA1) and GATA-binding protein 2 (GATA2). Lower concentrations of T3 had a stimulatory effect on hemin-induced hemoglobin production (1 and 10 nM), CD71 expression (0.1 nM), and α-globin mRNA expression (1 nM), while a higher concentration of T3 (100 nM) abrogated the stimulatory effect on these parameters. T3 at 100 nM did not affect cell viability and proliferation, suggesting that the abrogation of erythropoiesis enhancement was not due to toxicity. T3 at 100 nM also significantly inhibited expression of GATA2 and RXRα mRNA, compared to 1 nM T3. We conclude that a high concentration of T3 attenuates the classical stimulatory effect on erythropoiesis exerted by a low concentration of T3 in hemin-induced K562 cells. PMID:25787723

  7. AUF-1 and YB-1 independently regulate β-globin mRNA in developing erythroid cells through interactions with poly(A)-binding protein

    PubMed Central

    van Zalen, Sebastiaan; Lombardi, Alyssa A.; Jeschke, Grace R.; Hexner, Elizabeth O.; Russell, J. Eric

    2015-01-01

    The normal expression of β-globin protein in mature erythrocytes is critically dependent on post-transcriptional events in erythroid progenitors that ensure the high stability of β-globin mRNA. Previous work has revealed that these regulatory processes require AUF-1 and YB-1, two RNA-binding proteins that assemble an mRNP β-complex on the β-globin 3′UTR. Here, we demonstrate that the β-complex organizes during the erythropoietic interval when both β-globin mRNA and protein accumulate rapidly, implicating the importance of this regulatory mRNP to normal erythroid differentiation. Subsequent functional analyses link β-complex assembly to the half-life of β-globin mRNA in vivo, providing a mechanistic basis for this regulatory activity. AUF-1 and YB-1 appear to serve a redundant post-transcriptional function, as both β-complex assembly and β-globin mRNA levels are reduced by coordinate depletion of the two factors, and can be restored by independent rescue with either factor alone. Additional studies demonstrate that the β-complex assembles more efficiently on polyadenylated transcripts, implicating a model in which the β-complex enhances the binding of PABPC1 to the poly(A) tail, inhibiting mRNA deadenylation and consequently effecting the high half-life of β-globin transcripts in erythroid progenitors. These data specify a post-transcriptional mechanism through which AUF1 and YB1 contribute to the normal development of erythropoietic cells, as well as to non-hematopoietic tissues in which AUF1-and YB1-based regulatory mRNPs have been observed to assemble on heterologous mRNAs. PMID:25720531

  8. Candidate ligand for the c-kit transmembrane kinase receptor: KL, a fibroblast derived growth factor stimulates mast cells and erythroid progenitors.

    PubMed Central

    Nocka, K; Buck, J; Levi, E; Besmer, P

    1990-01-01

    The c-kit proto-oncogene encodes a transmembrane tyrosine kinase receptor for an unidentified ligand and is allelic with the murine white-spotting locus (W). W mutations affect melanogenesis, gametogenesis and hematopoiesis during development and in adult life. Cellular targets of W mutations in hematopoiesis include distinct cell populations in the erythroid and mast cell lineages as well as stem cells. In the absence of interleukin-3 (IL-3) mast cells derived from normal mice but not from W mutant mice can be maintained by co-culture with 3T3 fibroblasts. Based on the defective proliferative response of W mast cells in the 3T3 fibroblast co-culture system it had been proposed that fibroblasts produce the c-kit ligand. We have used a mast cell proliferation assay to purify a 30 kd protein, designated KL, from conditioned medium of Balb/3T3 fibroblasts to apparent homogeneity. KL stimulates the proliferation of normal bone marrow derived mast cells but not mast cells from W mice, although both normal and mutant mast cells respond similarly to IL-3. Connective tissue-type mast cells derived from the peritoneal cavity of normal mice were found to express a high level of c-kit protein on their surface and to proliferate in response to KL. The effect of KL on erythroid progenitor cells was investigated as well. In combination with erythropoietin, KL was found to stimulate early erythroid progenitors (BFU-E) from fetal liver and spleen cells but not from bone marrow cells of adult mice and from fetal liver cells of W/W mice.(ABSTRACT TRUNCATED AT 250 WORDS) Images Fig. 1. Fig. 3. Fig. 5. Fig. 7. PMID:1698611

  9. An Understanding of Sustainability and Education for Sustainable Development among German Student Teachers and Trainee Teachers of Chemistry

    ERIC Educational Resources Information Center

    Burmeister, Mareike; Eilks, Ingo

    2013-01-01

    Sustainable development is a central concern of today's politics across the world. Different political agendas have been developed to promote sustainability and make it a political goal worldwide. As stated in Agenda 21, the political debate seems to agree that education has to play a key role in achieving sustainability. But practices…

  10. Education for Sustainability-Challenges and Opportunities: The Case of RCEs (Regional Centres of Expertise in Education for Sustainable Development)

    ERIC Educational Resources Information Center

    Wade, Ros

    2016-01-01

    This article will focus on the challenges of leadership and management of a key initiative of the 20052014 UN Decade of Education for Sustainable Development (DESD), namely the Regional Centres of Expertise in Education for Sustainability (RCEs). It will argue that in order to achieve sustainability, there is a need to move away from outdated…

  11. MYB controls erythroid versus megakaryocyte lineage fate decision through the miR-486-3p-mediated downregulation of MAF

    PubMed Central

    Bianchi, E; Bulgarelli, J; Ruberti, S; Rontauroli, S; Sacchi, G; Norfo, R; Pennucci, V; Zini, R; Salati, S; Prudente, Z; Ferrari, S; Manfredini, R

    2015-01-01

    The transcription factor MYB has a key role in hematopoietic progenitor cells (HPCs) lineage choice, by enhancing erythropoiesis at the expense of megakaryopoiesis. We previously demonstrated that MYB controls erythroid versus megakaryocyte lineage decision by transactivating KLF1 and LMO2 expression. To further unravel the molecular mechanisms through which MYB affects lineage fate decision, we performed the integrative analysis of miRNA and mRNA changes in MYB-silenced human primary CD34+ HPCs. Among the miRNAs with the highest number of predicted targets, we focused our studies on hsa-miR-486-3p by demonstrating that MYB controls miR-486-3p expression through the transactivation of its host gene, ankyrin-1 (ANK1) and that miR-486-3p affects HPCs commitment. Indeed, overexpression and knockdown experiments demonstrated that miR-486-3p supports the erythropoiesis while restraining the megakaryopoiesis. Of note, miR-486-3p also favors granulocyte differentiation while repressing the macrophage differentiation. To shed some light on the molecular mechanisms through which miR-486-3p affects HPCs lineage commitment, we profiled the gene expression changes upon miR-486-3p overexpression in CD34+ cells. Among the genes downregulated in miR-486-3p-overexpressing HPCs and computationally predicted to be miR-486-3p targets, we identified MAF as a miR-486-3p target by 3′UTR luciferase reporter assay. Noteworthy, MAF overexpression was able to partially reverse the effects of miR-486-3p overexpression on erythroid versus megakaryocyte lineage choice. Moreover, the MYB/MAF co-silencing constrained the skewing of erythroid versus megakaryocyte lineage commitment in MYB-silenced CD34+ cells, by restraining the expansion of megakaryocyte lineage while partially rescuing the impairment of erythropoiesis. Therefore, our data collectively demonstrate that MYB favors erythropoiesis and restrains megakaryopoiesis through the transactivation of miR-486-3p expression and the

  12. Biased, non-equivalent gene-proximal and -distal binding motifs of orphan nuclear receptor TR4 in primary human erythroid cells.

    PubMed

    Shi, Lihong; Sierant, M C; Gurdziel, Katherine; Zhu, Fan; Cui, Shuaiying; Kolodziej, Katarzyna E; Strouboulis, John; Guan, Yuanfang; Tanabe, Osamu; Lim, Kim-Chew; Engel, James Douglas

    2014-05-01

    We previously reported that TR2 and TR4 orphan nuclear receptors bind to direct repeat (DR) elements in the ε- and γ-globin promoters, and act as molecular anchors for the recruitment of epigenetic corepressors of the multifaceted DRED complex, thereby leading to ε- and γ-globin transcriptional repression during definitive erythropoiesis. Other than the ε- and γ-globin and the GATA1 genes, TR4-regulated target genes in human erythroid cells remain unknown. Here, we identified TR4 binding sites genome-wide using chromatin immunoprecipitation followed by massively parallel sequencing (ChIP-seq) as human primary CD34(+) hematopoietic progenitors differentiated progressively to late erythroid precursors. We also performed whole transcriptome analyses by RNA-seq to identify TR4 downstream targets after lentiviral-mediated TR4 shRNA knockdown in erythroid cells. Analyses from combined ChIP-seq and RNA-seq datasets indicate that DR1 motifs are more prevalent in the proximal promoters of TR4 direct target genes, which are involved in basic biological functions (e.g., mRNA processing, ribosomal assembly, RNA splicing and primary metabolic processes). In contrast, other non-DR1 repeat motifs (DR4, ER6 and IR1) are more prevalent at gene-distal TR4 binding sites. Of these, approximately 50% are also marked with epigenetic chromatin signatures (such as P300, H3K27ac, H3K4me1 and H3K27me3) associated with enhancer function. Thus, we hypothesize that TR4 regulates gene transcription via gene-proximal DR1 sites as TR4/TR2 heterodimers, while it can associate with novel nuclear receptor partners (such as RXR) to bind to distant non-DR1 consensus sites. In summary, this study reveals that the TR4 regulatory network is far more complex than previously appreciated and that TR4 regulates basic, essential biological processes during the terminal differentiation of human erythroid cells. PMID:24811540

  13. Antisense myb inhibition of purified erythroid progenitors in development and differentiation is linked to cycling activity and expression of DNA polymerase alpha

    SciTech Connect

    Valtieri, M.; Venturelli, D.; Care, A.; Fossati, C.; Pelosi, E.; Labbaye, C.; Mattia, G.; Gewirtz, A.M.; Calabretta, B.; Peschle, C. )

    1991-03-15

    These studies aimed to determine the expression and functional role of c-myb in erythroid progenitors with different cycling activities. In the first series of experiments the erythroid burst-forming unit (BFU-E) and colony-forming unit (CFU-E) populations from adult peripheral blood (PB), bone marrow (BM), and embryonic-fetal liver (FL) were treated with either c-myb antisense oligomers or 3H-thymidine (3H-TdR). A direct correlation was always observed between the inhibitory effect of anti-myb oligomers and the level of cycling activity. Thus, the inhibitory effect of antisense c-myb on the number of BFU-E colonies was 28.3% +/- 15.8% in PB, 53.4% +/- 9.3% in BM, and 68.2% +/- 24.5% in FL. Both adult and embryonic CFU-E were markedly inhibited. Using purified PB progenitors, we observed a similar pattern, although with slightly lower inhibitory effects. In the 3H-TdR suicide assay the killing index of BFU-E was 8.9% +/- 4.2% in PB, 29.4% +/- 6.5% in BM, and 40.1% +/- 9.6% in FL. The values for adult and embryonic CFU-E were 55.7% +/- 7.9% and 60.98% +/- 6.6%, respectively. We then investigated the kinetics of c-myb mRNA level during the erythroid differentiation of purified adult PB and FL BFU-E, as evaluated in liquid-phase culture by reverse transcription-polymerase chain reaction. Adult erythroid precursors showed a gradual increase of c-myb mRNA from day 4 through day 8 of culture and a sharp decrease at later times, whereas the expression of c-myb mRNA and protein in differentiation embryonic precursors peaked 2 days earlier. In both cases, c-myb mRNA level peaked at the CFU-E stage of differentiation. Finally, highly purified adult PB BFU-E were stimulated into cycling by a 3-day treatment with interleukin-3 in liquid phase: both the sensitivity to c-myb antisense oligomers and the 3H-TdR suicide index showed a gradual, strictly parallel increase.

  14. Is Sustainable Remediation Now a Self-Sustaining Process? an International Progress Report

    NASA Astrophysics Data System (ADS)

    Smith, J. W. N.

    2014-12-01

    Sustainable remediation - the consideration of environmental, social and economic factors associated with soil and groundwater risk-management options, to help select the best overall solution - has been a rapidly evolving topic in recent years. The first published reference[1] to 'sustainable remediation' was in the title of a 1999 conference paper by Kearney et al., (1999), but activity really accelerated in the middle-late 2000's, with establishment of a number of collaborative sustainable remediation groups and fora, and increased publication rates in the peer reviewed literature (Fig 1). Figure 1. Journal paper publications with search term 'sustainable remediation' (SCOPUS survey, 17 July 2014) This presentation will review the international progress of sustainable remediation concept development and application in regulatory and corporate decision-making processes. It will look back at what has already been achieved, provide an update on the latest initiatives and developments, and look forward to what the future of sustainable remediation might look like. Specifically it will describe: Sustainable remediation frameworks: synergies and international collaboration; Latest guidance and tools developed by the various sustainable remediation organisations (SuRFs), including the SuRF-UK Best Management Practices and Tier 1 Briefcase; Best practice standard development by ASTM and ISO; Regulatory acceptance of sustainable remediation, including incorporation into legislation, and the NICOLE - Common Forum Joint statement on 'risk-informed and sustainable remediation' in Europe; Examples of corporate adoption of sustainable remediation principles. The presentation will conclude with a look forward to a vision of sustainable remediation in 2020.

  15. Youth Action Council on Sustainable Innovation (YACSI) Report: Making Innovation Sustainable Among Youth in Canada.

    ERIC Educational Resources Information Center

    2002

    A study surveyed 241 high-achieving youth aged 15-25 regarding how innovation can be made sustainable among youth in Canada. Results were insightful and pointed to actionable steps for the Youth Action Council for Sustainable Innovation and the federal government. Findings indicated the following: youth can be more innovative if they have the…

  16. Competences for Sustainable Development and Sustainability: Significance and Challenges for ESD

    ERIC Educational Resources Information Center

    Mochizuki, Yoko; Fadeeva, Zinaida

    2010-01-01

    Purpose--The purpose of this paper is to draw attention of the education for sustainable development (ESD) community to recent discussions on competence approaches and to examine the adequacy of a competence-based model as the means of achieving educational and societal transformation towards sustainability. The paper analyses and highlights some…

  17. Comparing Science Achievement Constructs: Targeted and Achieved

    ERIC Educational Resources Information Center

    Ferrara, Steve; Duncan, Teresa

    2011-01-01

    This article illustrates how test specifications based solely on academic content standards, without attention to other cognitive skills and item response demands, can fall short of their targeted constructs. First, the authors inductively describe the science achievement construct represented by a statewide sixth-grade science proficiency test.…

  18. Sustainable development - lessons from success

    SciTech Connect

    Reid, W.V.C. )

    1989-05-01

    This article examines the push of development agencies and multilateral development banks in developing countries to achieve economic, political and social sustainability without considering long-term environmental costs. A case in point is dams built for irrigation and hydroelectric power; the benefits are outweighed by the environmental costs of salt intrusion, delta erosion, drying of downstream lakes and channel deepening as well as the effects of displacement of people. The information and technologies that form the basis of ecologically sustainable development already exist. Energy efficiency projects could reduce the balance of trade deficits in developing nations. In addition, great advances in agricultural, forest and range productivity could be achieved at very low capital costs through soil and water conservation techniques, intercropping, agroforestry and organic fertilization.

  19. Varieties of Achievement Motivation.

    ERIC Educational Resources Information Center

    Kukla, Andre; Scher, Hal

    1986-01-01

    A recent article by Nicholls on achievement motivation is criticized on three points: (1) definitions of achievement motives are ambiguous; (2) behavioral consequences predicted do not follow from explicit theoretical assumptions; and (3) Nicholls's account of the relation between his theory and other achievement theories is factually incorrect.…

  20. Motivation and School Achievement.

    ERIC Educational Resources Information Center

    Maehr, Martin L.; Archer, Jennifer

    Addressing the question, "What can be done to promote school achievement?", this paper summarizes the literature on motivation relating to classroom achievement and school effectiveness. Particular attention is given to how values, ideology, and various cultural patterns impinge on classroom performance and serve to enhance motivation to achieve.…

  1. Mobility and Reading Achievement.

    ERIC Educational Resources Information Center

    Waters, Theresa Z.

    A study examined the effect of geographic mobility on elementary school students' achievement. Although such mobility, which requires students to make multiple moves among schools, can have a negative impact on academic achievement, the hypothesis for the study was that it was not a determining factor in reading achievement test scores. Subjects…

  2. PASS and Reading Achievement.

    ERIC Educational Resources Information Center

    Kirby, John R.

    Two studies examined the effectiveness of the PASS (Planning, Attention, Simultaneous, and Successive cognitive processes) theory of intelligence in predicting reading achievement scores of normally achieving children and distinguishing children with reading disabilities from normally achieving children. The first study dealt with predicting…

  3. 2010 Campus Sustainability Review

    ERIC Educational Resources Information Center

    Association for the Advancement of Sustainability in Higher Education, 2011

    2011-01-01

    With this review of campus sustainability efforts in 2010, the editors aim to give readers--those who are often immersed in the day-to-day particulars of sustainability efforts--the same chance to take a step back and take a broader look at where they stand with sustainability in higher education. This inaugural 2010 Campus Sustainability Review…

  4. Organizing for Sustainability

    ERIC Educational Resources Information Center

    Brown, William M.; Hamburger, Michael W.

    2012-01-01

    A successful campus sustainability effort catalyzes broad engagement of the campus community and integration of sustainability principles into the academic and operational components of campus life. Although many universities have embraced sustainability as a new core value, others have been more sluggish in adopting sustainability principles to…

  5. SUSTAINABILITY AND COMPLEX SYSTEMS

    EPA Science Inventory

    The important question in sustainability is not whether the world is sustainable, but whether a humanly acceptable regime of the world is sustainable. World commission on environment and development defines sustainability as ‘development that meets the needs of the present withou...

  6. Sustaining Writing Theory

    ERIC Educational Resources Information Center

    Patrick, Amy M.

    2010-01-01

    This article examines ways in which the fundamentals of both writing studies and sustainability studies overlap and complement each other, ultimately moving toward a theory of writing that not only is sustainable, but that also sustains writing practice across a variety of areas. For example, in order to be sustainable, both writing and…

  7. Focus on sustainability.

    PubMed

    Thompson, R J; Godiksen, L; Hansen, G; Gustafson, D J; Brinkerhoff, D W; Ingle, M D; Rounds, T; Wing, H

    1990-01-01

    In recent years, sustainability has become one of the most critical concepts in international development and is having a dramatic impact on the way development is conceptualized and carried out. The US Agency for International Development (USAID) is incorporating this concept into its programs and projects. Factors encouraging sustainability of projects and programs include host government policies that support or constrain program objectives, national and/or local commitment to project goals, managerial leadership that helps shape improved policies, collaboration at all staff levels in program management, financial resources that cover program operational costs, appropriate program technology, integration of the program with the social and cultural setting of the country, community involvement in the program, sound environmental management, technical assistance oriented to transferring skills and increasing institutional capacity, perception by the host country that the project is "effective," training provided by the project to transfer skill needed for capacity-building, integration of the program into existing institutional framework, and external political, economic and environmental factors. Impediments to sustainability are often inherent in the donor agency's programming process. This includes the implicit assumption that program objectives can be accomplished in a relatively short time frame, when in fact capacity-building requires a lengthy commitment. USAID professionals are pressured to show near-term results which emphasize outputs rather than purpose and goal-level accomplishments achievable only after extensive effort. The emphasis on obligating money and on the project paper as a sales document leads project designers to talk with a great deal more certainty about project results than is warranted by the complex development situation. Uncertainty and flexibility should be designed into projects so activities and objects can change as more

  8. In utero and in vitro effects of benzene and its metabolites on erythroid differentiation and the role of reactive oxygen species

    SciTech Connect

    Badham, Helen J.; Winn, Louise M.

    2010-05-01

    Benzene is a ubiquitous occupational and environmental toxicant. Exposures to benzene both prenatally and during adulthood are associated with the development of disorders such as aplastic anemia and leukemia. Mechanisms of benzene toxicity are unknown; however, generation of reactive oxygen species (ROS) by benzene metabolites may play a role. Little is known regarding the effects of benzene metabolites on erythropoiesis. Therefore, to determine the effects of in utero exposure to benzene on the growth and differentiation of fetal erythroid progenitor cells (CFU-E), pregnant CD-1 mice were exposed to benzene and CFU-E numbers were assessed in fetal liver (hematopoietic) tissue. In addition, to determine the effect of benzene metabolite-induced ROS generation on erythropoiesis, HD3 chicken erythroblast cells were exposed to benzene, phenol, or hydroquinone followed by stimulation of erythrocyte differentiation. Our results show that in utero exposure to benzene caused significant alterations in female offspring CFU-E numbers. In addition, exposure to hydroquinone, but not benzene or phenol, significantly reduced the percentage of differentiated HD3 cells, which was associated with an increase in ROS. Pretreatment of HD3 cells with polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) prevented hydroquinone-induced inhibition of erythropoiesis, supporting the hypothesis that ROS generation is involved in the development of benzene erythrotoxicity. In conclusion, this study provided evidence that ROS generated as a result of benzene metabolism may significantly alter erythroid differentiation, potentially leading to the development of Blood Disorders.

  9. Thalidomide is more efficient than sodium butyrate in enhancing GATA-1 and EKLF gene expression in erythroid progenitors derived from HSCs with β-globin gene mutation

    PubMed Central

    Jalali Far, Mohammad Ali; Dehghani Fard, Ali; Hajizamani, Saiedeh; Mossahebi-Mohammadi, Majid; Yaghooti, Hamid; Saki, Najmaldin

    2016-01-01

    Background: Efficient induction of fetal hemoglobin (HbF) is considered as an effective therapeutic approach in beta thalassemia. HbF inducer agents can induce the expression of γ-globin gene and produce high levels of HbF via different epigenetic and molecular mechanisms. Thalidomide and sodium butyrate are known as HbF inducer drugs. Material and methods: CD133+ stem cells were isolated from umbilical cord blood of a newborn with minor β-thalassemia in order to evaluate the effects of these two drugs on the in vitro expression of GATA-1 and EKLF genes as erythroid transcription factors. CD133+ stem cells were expanded and differentiated into erythroid lineage and then treated with thalidomide and sodium butyrate and finally analyzed by quantitative real-time PCR. Statistical analysis was performed using student’s t-test by SPSS software. Results: Thalidomide and sodium butyrate increased GATA-1 and EKLF gene expression, compared to the non-treated control (P<0.05). Conclusion: Thalidomide was more efficient than sodium butyrate in augmenting expression of GATA-1 and EKLF genes. It seems that GATA-1 and EKLF have crucial roles in the efficient induction of HbF by thalidomide. PMID:27047649

  10. The major human erythroid DNA-binding protein (GF-1): Primary sequence and localization of the gene to the X chromosome

    SciTech Connect

    Zon, L.I.; Tsai, S.F.; Burgess, S.; Orkin, S.H. Howard Hughes Medical Institute, Boston, MA ); Matsudaira, P. ); Bruns, G.A.P. )

    1990-01-01

    Genes expressed in erythroid cells contain binding sites for a cell-specific nuclear factor, GF-1 (NF-E1, Eryf 1), believed to be an important transcriptional regulator. Previously the authors characterized murine GF-1 as a 413-amino acid polypeptide containing two cysteine-cysteine regions reminiscent of zinc-finger DNA-binding domains. By cross-hybridization to the finger domain of murine GF-1 they have isolated cDNA encoding the human homolog. Peptide sequencing of purified human GF-1 confirmed the authenticity of the human cDNA. The predicted primary sequence of human GF-1 is highly similar to that of murine GF-1, particularly in the DNA-binding region. Although the DNA-binding domains of human, murine, and chicken proteins are remarkably conserved, the mammalian polypeptides are strikingly divergent from the avian counterpart in other regions, most likely those responsible for transcriptional activation. By hybridization to panels of human-rodent DNAs they have assigned the human GF-1 locus to Xp21-11. The localization of the gene to the X chromosome has important implications for hereditary persistence of fetal hemoglobin syndromes unlinked to the {beta}-globin cluster and for genetic experiments designed to test the role of the factor in erythroid cell gene expression.

  11. PLC-beta 1 regulates the expression of miR-210 during mithramycin-mediated erythroid differentiation in K562 cells

    PubMed Central

    Fiume, Roberta; Blalock, William; Matteucci, Alessandro; Ramazzotti, Giulia; McCubrey, James A.; Cocco, Lucio; Faenza, Irene

    2014-01-01

    PLC-beta 1 (PLCβ1) inhibits in human K562 cells erythroid differentiation induced by mithramycin (MTH) by targeting miR-210 expression. Inhibition of miR-210 affects the erythroid differentiation pathway and it occurs to a greater extent in MTH-treated cells. Overexpression of PLCβ1 suppresses the differentiation of K562 elicited by MTH as demonstrated by the absence of γ-globin expression. Inhibition of PLCβ1 expression is capable to promote the differentiation process leading to a recovery of γ-globin gene even in the absence of MTH. Our experimental evidences suggest that PLCβ1 signaling regulates erythropoiesis through miR-210. Indeed overexpression of PLCβ1 leads to a decrease of miR-210 expression after MTH treatment. Moreover miR-210 is up-regulated when PLCβ1 expression is down-regulated. When we silenced PKCα by RNAi technique, we found a decrease in miR-210 and γ-globin expression levels, which led to a severe slowdown of cell differentiation in K562 cells and these effects were the same encountered in cells overexpressing PLCβ1. Therefore we suggest a novel role for PLCβ1 in regulating miR-210 and our data hint at the fact that, in human K562 erythroleukemia cells, the modulation of PLCβ1 expression is able to exert an impairment of normal erythropoiesis as assessed by γ-globin expression. PMID:24962066

  12. Intrinsic defects in erythroid cells from familial hemophagocytic lymphohistiocytosis type 5 patients identify a role for STXBP2/Munc18-2 in erythropoiesis and phospholipid scrambling.

    PubMed

    Kostova, Elena B; Beuger, Boukje M; Veldthuis, Martijn; van der Werff Ten Bosch, Jutte; Kühnle, Ingrid; van den Akker, Emile; van den Berg, Timo K; van Zwieten, Rob; van Bruggen, Robin

    2015-12-01

    Familial hemophagocytic lymphohistiocytosis type 5 (FHL-5) is a rare genetic disorder caused by mutations in STXBP2/Munc18-2. Munc18-2 plays a role in the degranulation machinery of natural killer cells and cytotoxic T lymphocytes. Mutations in STXBP2/Munc18-2 lead to impaired killing of target cells by natural killer cells and cytotoxic T lymphocytes, which in turn results in elevated levels of the inflammatory cytokine interferon γ, macrophage activation, and hemophagocytosis. Even though patients with FHL-5 present with anemia and hemolysis, no link between the disease and the erythroid lineage has been established. Here we report that red blood cells express Munc18-2 and that erythroid cells from patients with FHL-5 exhibit intrinsic defects caused by STXBP2/Munc18-2 mutations. Red blood cells from patients with FHL-5 expose less phosphatidylserine on their surface upon Ca(2+) ionophore ionomycin treatment. Furthermore, cultured erythroblasts from patients with FHL-5 display defective erythropoiesis characterized by decreased CD235a expression and aberrant cell morphology. PMID:26320718

  13. Transcriptional Activity of Erythroid Kruppel-like Factor (EKLF/KLF1) Modulated by PIAS3 (Protein Inhibitor of Activated STAT3)*

    PubMed Central

    Siatecka, Miroslawa; Soni, Shefali; Planutis, Antanas; Bieker, James J.

    2015-01-01

    Erythroid Kruppel-like factor (EKLF or KLF1) is a transcription factor crucial for red cell development that is directly involved in regulation of a large number of erythroid genes. EKLF serves mostly as an activator of expression of these genes; however, it can act also as a repressor. Here, we present evidence that EKLF interacts with proteins from the PIAS (protein inhibitor of activated STAT) family that convey repressive activity to EKLF in the absence of sumoylation. Our studies identify PIAS3 as a transcriptional corepressor of EKLF for at least a subset of its target genes during erythropoiesis (e.g. β-globin, α-hemoglobin stabilizing protein). We demonstrate an interaction between EKLF and PIAS proteins confirmed by in vivo coimmunoprecipitation assays with both exogenous and endogenous proteins. We identified an LXXLL signature motif located near the N terminus of PIAS proteins that, although not involved in the EKLF-PIAS3 interaction, is required for the transrepression activity. Knockdown of endogenous PIAS3 accelerates differentiation of both murine erythroleukemia cells, as well as fetal liver cells, whereas an increase in PIAS3 levels inhibits this increase. Using chromatin immunoprecipitation assays, we show that PIAS3 preferentially occupies the β-globin promoter in undifferentiated murine erythroleukemia cells. Together these results demonstrate that an interaction between EKLF and PIAS3 provides a novel mode of regulation of EKLF activity in the absence of sumolylation and furthermore shows an important involvement of PIAS proteins in erythropoiesis. PMID:25713074

  14. Cis-vaccenic acid induces differentiation and up-regulates gamma globin synthesis in K562, JK1 and transgenic mice erythroid progenitor stem cells.

    PubMed

    Aimola, Idowu A; Inuwa, Hajiya M; Nok, Andrew J; Mamman, Aisha I; Bieker, James J

    2016-04-01

    Gamma globin induction remains a promising pharmacological therapeutic treatment mode for sickle cell anemia and beta thalassemia, however Hydroxyurea remains the only FDA approved drug which works via this mechanism. In this regard, we assayed the γ-globin inducing capacity of Cis-vaccenic acid (CVA). CVA induced differentiation of K562, JK1 and transgenic mice primary bone marrow hematopoietic progenitor stem cells. CVA also significantly up-regulated γ-globin gene expression in JK-1 and transgenic mice bone marrow erythroid progenitor stem cells (TMbmEPSCs) but not K562 cells without altering cell viability. Increased γ-globin expression was accompanied by KLF1 suppression in CVA induced JK-1 cells. Erythropoietin induced differentiation of JK-1 cells 24h before CVA induction did not significantly alter CVA induced differentiation and γ-globin expression in JK-1 cells. Inhibition of JK-1 and Transgenic mice bone marrow erythroid progenitor stem cells Fatty acid elongase 5 (Elovl5) and Δ(9) desaturase suppressed the γ-globin inductive effects of CVA. CVA treatment failed to rescue γ-globin expression in Elovl5 and Δ(9)-desaturase inhibited cells 48 h post inhibition in JK-1 cells. The data suggests that CVA directly modulates differentiation of JK-1 and TMbmEPSCs, and indirectly modulates γ-globin gene expression in these cells. Our findings provide important clues for further evaluations of CVA as a potential fetal hemoglobin therapeutic inducer. PMID:26879870

  15. Overactivation of the nuclear factor (erythroid-derived 2)-like 2-antioxidant response element pathway in hepatocytes decreases hepatic ischemia/reperfusion injury in mice.

    PubMed

    Lee, Lung-Yi; Harberg, Calvin; Matkowskyj, Kristina A; Cook, Shelly; Roenneburg, Drew; Werner, Sabine; Johnson, Jeffrey; Foley, David P

    2016-01-01

    Hepatic ischemia/reperfusion injury (IRI) is a critical component of hepatic surgery. Oxidative stress has long been implicated as a key player in IRI. In this study, we examine the cell-specific role of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-antioxidant response element pathway in warm hepatic IRI. Nrf2 knockout (KO) and wild-type (WT) animals and novel transgenic mice expressing a constitutively active nuclear factor (erythroid-derived 2)-like 2 (caNrf2) mutant in hepatocytes (AlbCre+/caNrf2+) and their littermate controls underwent partial hepatic ischemia or sham surgery. The animals were killed 6 hours after reperfusion, and their serum and tissue were collected for analysis. As compared to WT animals after ischemia/reperfusion (IR), Nrf2 KO mice had increased hepatocellular injury with increased serum alanine aminotransferase and aspartate aminotransferase, Suzuki score, apoptosis, an increased inflammatory infiltrate, and enhanced inflammatory cytokine expression. On the other hand, AlbCre+/caNrf2+ that underwent IR had significantly reduced serum transaminases, less necrosis on histology, and a less pronounced inflammatory infiltrate and inflammatory cytokine expression as compared to the littermate controls. However, there were no differences in apoptosis. Taken together, Nrf2 plays a critical role in our murine model of warm hepatic IRI, with Nrf2 deficiency exacerbating hepatic IRI and hepatocyte-specific Nrf2 overactivation providing protection against warm hepatic IRI. PMID:26285140

  16. Achieving clinical integration.

    PubMed

    Redding, John

    2013-11-01

    To develop an effective and sustainable clinically integrated network (CIN) that positions a healthcare organization for value-based payment and other effects of healthcare reform, leaders of CIN initiatives should: Embrace progress rather than perfection; Constrain the development timeline by project managing in reverse; Ensure that physician leaders play an oversight role in the development process. PMID:24340650

  17. Achieving permanency for LGBTQ youth.

    PubMed

    Jacobs, Jill; Freundlich, Madelyn

    2006-01-01

    This article brings together two significant efforts in the child welfare field: achieving permanence for youth in out-of-home care and meeting the needs of lesbian, gay, bisexual, transgender and questioning (LGBTQ) youth. During the past several years, a national movement has taken place to assure all children and youth have a permanent family connection before leaving the child welfare system; however, LGBTQ youth are not routinely included in the permanency discussions. At the same time, efforts in addressing the needs of LGBTQ youth have increased, but permanency is rarely mentioned as a need. This article offers models of permanence and practices to facilitate permanence with LGBTQ youth and their families. It also offers a youth-driven, individualized process, using youth development principles to achieve relational, physical, and legal permanence. Reunification efforts are discussed, including services, supports, and education required for youth to return to their family of origin. For those who cannot return home, other family resources are explored. The article also discusses cultural issues as they affect permanence for LGBTQ youth, and, finally, addresses the need for ongoing support services to sustain and support permanency. PMID:16846117

  18. The Road to Sustainability. Sustainability Workbook

    ERIC Educational Resources Information Center

    Afterschool Alliance, 2002

    2002-01-01

    Sustainability seems generally thought to mean raising money. But money is only part of the equation. Money cannot be raised without a quality program, a quality program demonstrates results, effective results are based on sound management practices, etc. Sustainability therefore, is many things that in combination make something capable of…

  19. Sustaining Rural Communities through Sustainable Agriculture.

    ERIC Educational Resources Information Center

    Ikerd, John

    A 5-year collaborative project between Missouri, Michigan State, and Nebraska Universities to provide new opportunities for rural community self-development through sustainable agriculture had mixed results. This happened because community members did not understand the principles of sustainability, and because the extension education system was…

  20. Exploring the Ambiguity: What Faculty Leaders Really Think of Sustainability in Higher Education

    ERIC Educational Resources Information Center

    Wright, Tarah; Horst, Naomi

    2013-01-01

    Purpose: The purpose of this paper is to examine how a cohort of university faculty leaders in Canadian universities conceptualize sustainable development, sustainable universities, the role universities play in achieving a sustainable future, key issues facing the university, and the barriers to implementing sustainability initiatives on campus.…

  1. Heritability of Creative Achievement

    ERIC Educational Resources Information Center

    Piffer, Davide; Hur, Yoon-Mi

    2014-01-01

    Although creative achievement is a subject of much attention to lay people, the origin of individual differences in creative accomplishments remain poorly understood. This study examined genetic and environmental influences on creative achievement in an adult sample of 338 twins (mean age = 26.3 years; SD = 6.6 years). Twins completed the Creative…

  2. Confronting the Achievement Gap

    ERIC Educational Resources Information Center

    Gardner, David

    2007-01-01

    This article talks about the large achievement gap between children of color and their white peers. The reasons for the achievement gap are varied. First, many urban minorities come from a background of poverty. One of the detrimental effects of growing up in poverty is receiving inadequate nourishment at a time when bodies and brains are rapidly…

  3. States Address Achievement Gaps.

    ERIC Educational Resources Information Center

    Christie, Kathy

    2002-01-01

    Summarizes 2 state initiatives to address the achievement gap: North Carolina's report by the Advisory Commission on Raising Achievement and Closing Gaps, containing an 11-point strategy, and Kentucky's legislation putting in place 10 specific processes. The North Carolina report is available at www.dpi.state.nc.us.closingthegap; Kentucky's…

  4. Wechsler Individual Achievement Test.

    ERIC Educational Resources Information Center

    Taylor, Ronald L.

    1999-01-01

    This article describes the Wechsler Individual Achievement Test, a comprehensive measure of achievement for individuals in grades K-12. Eight subtests assess mathematics reasoning, spelling, reading comprehension, numerical operations, listening comprehension, oral expression, and written expression. Its administration, standardization,…

  5. Inverting the Achievement Pyramid

    ERIC Educational Resources Information Center

    White-Hood, Marian; Shindel, Melissa

    2006-01-01

    Attempting to invert the pyramid to improve student achievement and increase all students' chances for success is not a new endeavor. For decades, educators have strategized, formed think tanks, and developed school improvement teams to find better ways to improve the achievement of all students. Currently, the No Child Left Behind Act (NCLB) is…

  6. Achievement Test Program.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Trade and Industrial Education Service.

    The Ohio Trade and Industrial Education Achievement Test battery is comprised of seven basic achievement tests: Machine Trades, Automotive Mechanics, Basic Electricity, Basic Electronics, Mechanical Drafting, Printing, and Sheet Metal. The tests were developed by subject matter committees and specialists in testing and research. The Ohio Trade and…

  7. General Achievement Trends: Maryland

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  8. General Achievement Trends: Arkansas

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  9. General Achievement Trends: Idaho

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  10. General Achievement Trends: Nebraska

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  11. General Achievement Trends: Colorado

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  12. General Achievement Trends: Iowa

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  13. General Achievement Trends: Hawaii

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  14. General Achievement Trends: Kentucky

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  15. General Achievement Trends: Florida

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  16. General Achievement Trends: Texas

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  17. General Achievement Trends: Oregon

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  18. General Achievement Trends: Virginia

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  19. Honoring Student Achievement

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    Is the concept of "honor roll" obsolete? The honor roll has always been a way for schools to recognize the academic achievement of their students. But does it motivate students? In this article, several elementary school principals share their views about honoring student achievement. Among others, Virginia principal Nancy Moga said that students…

  20. Aiming at Achievement.

    ERIC Educational Resources Information Center

    Martinez, Paul

    The Raising Quality and Achievement Program is a 3-year initiative to support further education (FE) colleges in the United Kingdom in their drive to improve students' achievement and the quality of provision. The program offers the following: (1) quality information and advice; (2) onsite support for individual colleges; (3) help with…

  1. Achieving Perspective Transformation.

    ERIC Educational Resources Information Center

    Nowak, Jens

    Perspective transformation is a consciously achieved state in which the individual's perspective on life is transformed. The new perspective serves as a vantage point for life's actions and interactions, affecting the way life is lived. Three conditions are basic to achieving perspective transformation: (1) "feeling" experience, i.e., getting in…

  2. Achieving Public Schools

    ERIC Educational Resources Information Center

    Abowitz, Kathleen Knight

    2011-01-01

    Public schools are functionally provided through structural arrangements such as government funding, but public schools are achieved in substance, in part, through local governance. In this essay, Kathleen Knight Abowitz explains the bifocal nature of achieving public schools; that is, that schools are both subject to the unitary Public compact of…

  3. General Achievement Trends: Tennessee

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  4. Achievement-Based Resourcing.

    ERIC Educational Resources Information Center

    Fletcher, Mike; And Others

    1992-01-01

    This collection of seven articles examines achievement-based resourcing (ABR), the concept that the funding of educational institutions should be linked to their success in promoting student achievement, with a focus on the application of ABR to postsecondary education in the United Kingdom. The articles include: (1) "Introduction" (Mick…

  5. Sustaining Cyberinfrastructure Interoperabililty

    NASA Astrophysics Data System (ADS)

    Moore, R. W.; Rajasekar, A.

    2015-12-01

    The National Science Foundation has initiated multiple cyberinfrastructure projects through the DataNet Parters, Data Infrastructure Building Blocks, Big Data Hubs, EarthCube, and XSEDE programs. Each project builds a component of cyberinfrastructure, such as collaboration environments, repositories, archives, union catalogs, or data manipulation services. The DataNet Federation Consortium (DFC) (datafed.org) has explored the types of interoperability mechanisms that are needed to build research collaboration environments that span the multiple NSF projects. Based on collaborations with each group, three basic mechanisms have proven to be sufficient: 1) Strong Federation: Tightly coupled federations in which shared name spaces are used for users and files along with communications based on well-defined protocols and API interfaces. Trust relationships based on policies play a major role in this federation. 2) Soft Federation: Loosly coupled federation where one system invokes remote services offered by another using service level communications. No name spaces are shared in such a federation. This type of federation is useful when well-defined services are available remotely on the internet. 3) Asynchronous Federation: Weakly coupled federation in which no direct interaction occurs between the systems. This level of federation is very extensible and flexible. Long-term sustainability can be achieved when the interoperability mechanisms enable interaction between old and new technologies - with the interactions being flexible or rigid depending upon the strength of trust needed between the systems. Sustaining cyberinfrastructure interoperability becomes feasible when the mechanisms enable the capture of the knowledge needed for interaction, without requiring changes to either sets of infrastructure. The DFC project has implemented all three types of federation to link services and systems based on the needs of the users.

  6. Did Tanzania Achieve the Second Millennium Development Goal? Statistical Analysis

    ERIC Educational Resources Information Center

    Magoti, Edwin

    2016-01-01

    Development Goal "Achieve universal primary education", the challenges faced, along with the way forward towards achieving the fourth Sustainable Development Goal "Ensure inclusive and equitable quality education and promote lifelong learning opportunities for all". Statistics show that Tanzania has made very promising steps…

  7. Transcriptional up-regulation of the mouse cytosolic glutathione peroxidase gene in erythroid cells is due to a tissue-specific 3' enhancer containing functionally important CACC/GT motifs and binding sites for GATA and Ets transcription factors.

    PubMed Central

    O'Prey, J; Ramsay, S; Chambers, I; Harrison, P R

    1993-01-01

    Nuclear run-on experiments have shown that the high level of expression of the mouse cytosolic glutathione peroxidase mRNA in erythroid cells is due to up-regulation of the gene at the transcriptional level. Studies of the chromatin structure around the cytosolic glutathione peroxidase gene have revealed a series of DNase I hypersensitive sites (DHSS) in the 3' flanking region of the gene in erythroid and other high-expression tissues that are lacking in low-expression cells, in addition to a DHSS over the promoter region in both high- and low-expression tissues. Functional transfection experiments have demonstrated that one of the 3' DHSS regions functions as an enhancer in erythroid cells but not in a low-expression epithelial cell line; and site-directed mutagenesis and footprinting experiments reveal that the activity of the erythroid cell-specific enhancer requires a cluster of binding sites for the CACC/GT box factors and the GATA and Ets families of transcription factors. Images PMID:8413228

  8. Sustainability Indicators and Metrics

    EPA Science Inventory

    Sustainability is about preserving human existence. Indicators and metrics are absolutely necessary to provide at least a semi-quantitative assessment of progress towards or away from sustainability. Otherwise, it becomes impossible to objectively assess whether progress is bei...

  9. BENCHMARKING SUSTAINABILITY ENGINEERING EDUCATION

    EPA Science Inventory

    The goals of this project are to develop and apply a methodology for benchmarking curricula in sustainability engineering and to identify individuals active in sustainability engineering education.

  10. Extended flow cytometry characterization of normal bone marrow progenitor cells by simultaneous detection of aldehyde dehydrogenase and early hematopoietic antigens: implication for erythroid differentiation studies

    PubMed Central

    Mirabelli, Peppino; Di Noto, Rosa; Lo Pardo, Catia; Morabito, Paolo; Abate, Giovanna; Gorrese, Marisa; Raia, Maddalena; Pascariello, Caterina; Scalia, Giulia; Gemei, Marica; Mariotti, Elisabetta; Del Vecchio, Luigi

    2008-01-01

    Background Aldehyde dehydrogenase (ALDH) is a cytosolic enzyme highly expressed in hematopoietic precursors from cord blood and granulocyte-colony stimulating factor mobilized peripheral blood, as well as in bone marrow from patients with acute myeloblastic leukemia. As regards human normal bone marrow, detailed characterization of ALDH+ cells has been addressed by one single study (Gentry et al, 2007). The goal of our work was to provide new information about the dissection of normal bone marrow progenitor cells based upon the simultaneous detection by flow cytometry of ALDH and early hematopoietic antigens, with particular attention to the expression of ALDH on erythroid precursors. To this aim, we used three kinds of approach: i) multidimensional analytical flow cytometry, detecting ALDH and early hematopoietic antigens in normal bone marrow; ii) fluorescence activated cell sorting of distinct subpopulations of progenitor cells, followed by in vitro induction of erythroid differentiation; iii) detection of ALDH+ cellular subsets in bone marrow from pure red cell aplasia patients. Results In normal bone marrow, we identified three populations of cells, namely ALDH+CD34+, ALDH-CD34+ and ALDH+CD34- (median percentages were 0.52, 0.53 and 0.57, respectively). As compared to ALDH-CD34+ cells, ALDH+CD34+ cells expressed the phenotypic profile of primitive hematopoietic progenitor cells, with brighter expression of CD117 and CD133, accompanied by lower display of CD38 and CD45RA. Of interest, ALDH+CD34- population disclosed a straightforward erythroid commitment, on the basis of three orders of evidences. First of all, ALDH+CD34- cells showed a CD71bright, CD105+, CD45- phenotype. Secondly, induction of differentiation experiments evidenced a clear-cut expression of glycophorin A (CD235a). Finally, ALDH+CD34- precursors were not detectable in patients with pure red cell aplasia (PRCA). Conclusion Our study, comparing surface antigen expression of ALDH+/CD34+, ALDH

  11. Sustainability of physical activity promoting environments and influences on sustainability following a structural intervention in residential children's homes.

    PubMed

    Dominick, Gregory M; Tudose, Alina; Pohlig, Ryan T; Saunders, Ruth P

    2016-04-01

    Research examining sustainability of health promotion programs within organizational settings is limited. The Environmental Interventions in Residential Children's Homes (ENRICH) was a structural intervention that trained Wellness Teams (WTs) within residential children's homes (RCH) to target environmental changes that promote physical activity (PA) among residential youth. This study examines the sustainability of PA promoting environments and influences on sustainability within RCHs. A sustainability survey was administered to 14 RCHs 2 years after receiving ENRICH. Variables included sustainability of PA promoting environments, Organizational Influences, perceived organizational and individual benefits, and implementation of PA and general (i.e. Global) wellness activities. Activities reported as sustained and barriers were used descriptively to inform sustainability. Path analyses explained the relationship between sustainability influences and sustainability of PA promoting environments. Sustainability was found in 8 of 14 (57%) RCHs. Sustained activities reflected greater Global versus PA implementation. Global implementation mediated the relationship between Organizational Influences and sustainability, which may have been more easily achieved since Global activities were most likely controlled by WTs and did not require extensive organizational support from RCH administrators. Results highlight the importance of defining and assessing different implementation types when measuring sustainability and influences on sustainability within RCHs organizations. PMID:26944869

  12. [Achievement of therapeutic objectives].

    PubMed

    Mantilla, Teresa

    2014-07-01

    Therapeutic objectives for patients with atherogenic dyslipidemia are achieved by improving patient compliance and adherence. Clinical practice guidelines address the importance of treatment compliance for achieving objectives. The combination of a fixed dose of pravastatin and fenofibrate increases the adherence by simplifying the drug regimen and reducing the number of daily doses. The good tolerance, the cost of the combination and the possibility of adjusting the administration to the patient's lifestyle helps achieve the objectives for these patients with high cardiovascular risk. PMID:25043543

  13. Sustainable Learning Organizations

    ERIC Educational Resources Information Center

    Velazquez, Luis E.; Esquer, Javier; Munguia, Nora E.; Moure-Eraso, Rafael

    2011-01-01

    Purpose: The purpose of this paper is to debate how companies may better become a sustainable learning organization by offering the most used and insightful concepts of sustainability. Design/methodology/approach: Through literature review, learning organization and sustainability perspectives are explored and compared. Findings: Learning…

  14. Measuring Educational Sustainability

    ERIC Educational Resources Information Center

    Selvanathan, Rani G.

    2013-01-01

    There are many definitions that are attributable to the meaning of sustainability. Sustainability can be viewed as long-lasting, effective result of a project, venture, action, or investment without consuming additional future resources. Because of the wide nature of its applicability, a universal measure of sustainability is hard to come by. This…

  15. Sustainability Statement and Policy

    ERIC Educational Resources Information Center

    Journal of Education for Sustainable Development, 2009

    2009-01-01

    This article presents nine resources that focus on environmental education and sustainability. These include: (1) "Sustainability Statement and Policy," Dalhousie University, Nova Scotia, Canada, 2009, which is available at http://office.sustainability.dal.ca/Governance; (2) "Climate Literacy: The Essential Principles of Climate Sciences,"…

  16. Custodial Operations: Green & Sustainable

    ERIC Educational Resources Information Center

    Campbell, J. Kirk

    2008-01-01

    Custodial Operations can have a significant impact on institutional green and sustainable goals if given the proper support and challenge. This article describes the green and sustainable custodial operations in place at Carleton College in Northfield, Minnesota. The article reviews the college's sustainable efforts on biodegradables, packaging,…

  17. Transferring Education for Sustainability

    ERIC Educational Resources Information Center

    Gafoor, Kunnathodi Abdul; Umer Farooque, T. K.

    2013-01-01

    Sustainability stands for sustaining the past, meeting needs of the present without compromising the ability to meet future needs. It should meet the individual and social needs, present and future needs local and global needs. A sustainable education that meets this requirements surely be a transferable education; an education that transfers from…

  18. Predicting Achievement and Motivation.

    ERIC Educational Resources Information Center

    Uguroglu, Margaret; Walberg, Herbert J.

    1986-01-01

    Motivation and nine other factors were measured for 970 students in grades five through eight in a study of factors predicting achievement and predicting motivation. Results are discussed. (Author/MT)

  19. Attractiveness and School Achievement

    ERIC Educational Resources Information Center

    Salvia, John; And Others

    1977-01-01

    The purpose of this study was to ascertain the relationship between rated attractiveness and two measures of school performance. Attractive children received significantly higher report cards and, to some degree, higher achievement test scores than their unattractive peers. (Author)

  20. Student Achievement and Motivation

    ERIC Educational Resources Information Center

    Flammer, Gordon H.; Mecham, Robert C.

    1974-01-01

    Compares the lecture and self-paced methods of instruction on the basis of student motivation and achieveme nt, comparing motivating and demotivating factors in each, and their potential for motivation and achievement. (Authors/JR)

  1. High expression levels of the "erythroid/brain" type glucose transporter (GLUT1) in the basal cells of human eye conjunctiva and oral mucosa reconstituted in culture.

    PubMed

    Gherzi, R; Melioli, G; De Luca, M; D'Agostino, A; Guastella, M; Traverso, C E; D'Anna, F; Franzi, A T; Cancedda, R

    1991-07-01

    The expression of the "erythroid/brain" type glucose transporter (GLUT1) seems to be a feature of "barrier" tissues, at least in humans. Recently, we reported that GLUT1 is highly expressed in the basal layers of either "authentic" human epidermis or human epidermis reconstituted in culture and that its expression seems to be related to keratinocyte differentiation. In this paper we demonstrate that GLUT1 is selectively expressed in the basal layers of either eye conjunctiva epithelia or oral mucosa, reconstituted in culture starting from 1-2 mm2 bioptic specimens of normal human tissue. GLUT1 mRNA and protein levels are very high in conjunctiva and oral mucosa, 2-3 times higher than in epidermis reconstituted in culture. Taking into account its localization at the border of tissues not directly vascularized, but metabolically active, GLUT1 could play an important role in controlling the entry of glucose into these firmly guarded tissues. PMID:2055270

  2. Performance sustaining intracortical neural prostheses

    NASA Astrophysics Data System (ADS)

    Nuyujukian, Paul; Kao, Jonathan C.; Fan, Joline M.; Stavisky, Sergey D.; Ryu, Stephen I.; Shenoy, Krishna V.

    2014-12-01

    Objective. Neural prostheses, or brain-machine interfaces, aim to restore efficient communication and movement ability to those suffering from paralysis. A major challenge these systems face is robust performance, particularly with aging signal sources. The aim in this study was to develop a neural prosthesis that could sustain high performance in spite of signal instability while still minimizing retraining time. Approach. We trained two rhesus macaques implanted with intracortical microelectrode arrays 1-4 years prior to this study to acquire targets with a neurally-controlled cursor. We measured their performance via achieved bitrate (bits per second, bps). This task was repeated over contiguous days to evaluate the sustained performance across time. Main results. We found that in the monkey with a younger (i.e., two year old) implant and better signal quality, a fixed decoder could sustain performance for a month at a rate of 4 bps, the highest achieved communication rate reported to date. This fixed decoder was evaluated across 22 months and experienced a performance decline at a rate of 0.24 bps yr-1. In the monkey with the older (i.e., 3.5 year old) implant and poorer signal quality, a fixed decoder could not sustain performance for more than a few days. Nevertheless, performance in this monkey was maintained for two weeks without requiring additional online retraining time by utilizing prior days’ experimental data. Upon analysis of the changes in channel tuning, we found that this stability appeared partially attributable to the cancelling-out of neural tuning fluctuations when projected to two-dimensional cursor movements. Significance. The findings in this study (1) document the highest-performing communication neural prosthesis in monkeys, (2) confirm and extend prior reports of the stability of fixed decoders, and (3) demonstrate a protocol for system stability under conditions where fixed decoders would otherwise fail. These improvements to decoder

  3. Cell-specific overactivation of nuclear erythroid 2 p45-related factor 2-mediated gene expression in myeloid cells decreases hepatic ischemia/reperfusion injury.

    PubMed

    Lee, Lung-Yi; Harberg, Calvin; Matkowskyj, Kristina A; Cook, Shelly; Roenneburg, Drew; Werner, Sabine; Johnson, Delinda A; Johnson, Jeffrey A; Foley, David P

    2016-08-01

    Hepatic ischemia/reperfusion injury (IRI) is an unavoidable consequence of liver transplantation that can lead to postoperative hepatic dysfunction. Myeloid cells that include Kupffer cells, monocytes, and neutrophils contribute to the inflammatory response and cellular injury observed during hepatic IRI. We hypothesize that overactivation of the nuclear erythroid 2 p45-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in myeloid cells leads to decreased cellular damage after hepatic IRI. We constructed transgenic mice with constitutively active nuclear erythroid 2 p45-related factor 2 (caNrf2) that over activates the Nrf2-ARE pathway in myeloid cells (lysozyme M cre recombinase [LysMcre]+/caNrf2+, n = 9), and their littermate controls lacking transgene expression (LysMcre+/caNrf2-, n = 11). The mice underwent either sham or partial hepatic ischemia surgery, with 60 minutes of ischemia followed by 6 hours of reperfusion. After IRI, LysMcre+/caNrf2+ mice demonstrated significantly decreased serum alanine aminotransferase and decreased areas of necrosis. Immunohistochemistry and immunoblot of caspase 3 showed a significantly decreased cleaved to full-length caspase 3 ratio in LysMcre+/caNrf2+ animals. Lymphocyte antigen 6 complex locus G and CD68 staining demonstrated reduced inflammatory cell infiltration. LysMcre+/caNrf2+ animals also had significantly decreased gene expression of proinflammatory cytokines, including interleukin (IL) 1β, IL6, tumor necrosis factor α, chemokine (C-C motif) ligand 2, and chemokine (C-X-C motif) ligand 10, and significantly decreased levels of 8-isoprostanes. In our model, Nrf2 overactivation in myeloid cells leads to decreased hepatocellular damage, necrosis, apoptosis, inflammation, and oxidative stress. Pharmacologic targeting of the Nrf2-ARE pathway in myeloid cells may be a novel strategy to mitigate hepatic IRI. Liver Transplantation 22 1115-1128 2016 AASLD. PMID:27113842

  4. Recombinant adeno-associated virus (rAAV)-mediated expression of a human gamma-globin gene in human progenitor-derived erythroid cells.

    PubMed Central

    Miller, J L; Donahue, R E; Sellers, S E; Samulski, R J; Young, N S; Nienhuis, A W

    1994-01-01

    Effective gene therapy for the severe hemoglobin (Hb) disorders, sickle-cell anemia and thalassemia, will require an efficient method to transfer, integrate, and express a globin gene in primary erythroid cells. To evaluate recombinant adeno-associated virus (rAAV) for this purpose, we constructed a rAAV vector encoding a human gamma-globin gene (pJM24/vHS432A gamma). Its 4725-nucleotide genome consists of two 180-bp AAV inverted terminal repeats flanking the core elements of hypersensitive sites 2, 3, and 4 from the locus control region of the beta-globin gene cluster, linked to a mutationally marked A gamma-globin gene (A gamma) containing native promoter and RNA processing signals. CD34+ human hematopoietic cells were exposed to rAAV particles at a multiplicity of infection of 500-1000 and cultured in semisolid medium containing several cytokines. A reverse transcriptase polymerase chain reaction assay distinguished mRNA signals derived from transduced and endogenous human gamma-globin genes. Twenty to 40% of human erythroid burst-forming unit-derived colonies expressed the rAAV-transduced A gamma-globin gene at levels 4-71% that of the endogenous gamma-globin genes. The HbF content of pooled control colonies was 26%, whereas HbF was 40% of the total in pooled colonies derived from rAAV transduced progenitors. These data establish that rAAV containing elements from the locus control region linked to a gamma-globin gene are capable of transferring and expressing that gene in primary human hematopoietic cells resulting in a substantial increase in HbF content. Images PMID:7524085

  5. Erythroid progenitor cells (CFU-E*) from Friend virus-infected mice undergo VVFe suicide in vitro in the absence of added erythropoietin

    SciTech Connect

    Del Rizzo, D.F.; Axelrad, A.A.

    1985-11-01

    The authors have investigated the effect of VVFe on the survival in suspension of erythropoietin (epo)-independent erythroid progenitor cells (CFU-E*) induced by Friend polycythemia virus (FV). Spleen cells from C3Hf/Bi mice previously infected with FV were exposed to carrier-free VVFe, and the survival of CFU-E* as a function of time in liquid medium was determined from the number of erythroid colonies that developed from these cells seeded in plasma cultures without added epo. The results showed that spleen CFU-E* were highly vulnerable to VVFe. Marrow CFU-E* behaved in a similar manner. The VVFe responsible for their suicide had been presented to the progenitor cells only during the 4-h period of incubation, after which they were washed and plated in excess nonradioactive iron. They therefore conclude that CFU-E* themselves, and not only their progeny, are capable of actively incorporating iron. Under the same conditions in the absence of added epo, the effect of VVFe on the survival of normal spleen or marrow CFU-E could not be assessed because two few normal CFU-E survived the incubation period. Normal bone marrow cells incubated in complete medium containing epo retained their capacity for erythrocytic colony formation, and CFU-E could then be shown to be vulnerable to VVFe. Thus, either the iron-incorporating system of normal CFU-E was inducible by epo, or else epo permitted survival of the CFU-E so that the activity of a constitutive iron-incorporating system could be recognized.

  6. Efficacy of Rapamycin as Inducer of Hb F in Primary Erythroid Cultures from Sickle Cell Disease and β-Thalassemia Patients.

    PubMed

    Pecoraro, Alice; Troia, Antonio; Calzolari, Roberta; Scazzone, Concetta; Rigano, Paolo; Martorana, Adriana; Sacco, Massimiliano; Maggio, Aurelio; Di Marzo, Rosalba

    2015-01-01

    Phenotypic improvement of hemoglobinopathies such as sickle cell disease and β-thalassemia (β-thal) has been shown in patients with high levels of Hb F. Among the drugs proposed to increase Hb F production, hydroxyurea (HU) is currently the only one proven to improve the clinical course of these diseases. However, Hb F increase and patient's response are highly variable, indicating that new pharmacological agents could be useful for patients not responding to HU or showing a reduction of response during long-term therapy. In this study we evaluated the efficacy of rapamycin, a lypophilic macrolide used for the prevention of acute rejection in renal transplant recipients, as an inducer of Hb F production. The analyses were performed in cultured erythroid progenitors from 25 sickle cell disease and 25 β-thal intermedia (β-TI) patients. The use of a quantitative Real-Time-polymerase chain reaction ReTi-PCR technique and high performance liquid chromatography (HPLC) allowed us to determine the increase in γ-globin mRNA expression and Hb F production in human erythroid cells treated with rapamycin. The results of our study demonstrated an increase in vitro of γ-globin mRNA expression in 15 sickle cell disease and 14 β-TI patients and a corresponding Hb F increase. The induction by rapamycin, even if lower or similar in most of samples analyzed, in some cases was higher than HU. These data suggest that rapamycin could be a good candidate to be used in vivo for the treatment of hemoglobinopathies. PMID:26016899

  7. Sustainability index for Taipei

    SciTech Connect

    Lee, Y.-J. . E-mail: yungjaanlee@pchome.com.tw; Huang Chingming . E-mail: michael@everwin.com.tw

    2007-08-15

    Sustainability indicators are an effective means of determining whether a city is moving towards sustainable development (SD). After considering the characteristics of Taipei, Taiwan, discussions with experts, scholars and government departments and an exhaustive literature review, this study selected 51 sustainability indicators corresponding to the socio-economic characteristic of Taipei City. Such indicators should be regarded as a basis for assessing SD in Taipei City. The 51 indicators are classified into economic, social, environmental and institutional dimensions. Furthermore, statistical data is adopted to identify the trend of SD from 1994 to 2004. Moreover, the sustainability index is calculated for the four dimensions and for Taipei as a whole. Analysis results demonstrate that social and environmental indicators are moving towards SD, while economic and institutional dimensions are performing relatively poorly. However, since 2002, the economic sustainability index has gradually moved towards SD. Overall, the Taipei sustainability index indicates a gradual trend towards sustainable development during the past 11 years.

  8. Health and sustainability.

    PubMed

    Kjӕrgård, Bente; Land, Birgit; Bransholm Pedersen, Kirsten

    2014-09-01

    In the present article, we explore how sustainable development strategies and health promotion strategies can be bridged. The concept of the 'duality of structure' is taken as our starting point for understanding the linkages between health promotion and sustainable development, and for uncovering the structural properties or conditions which either enable or constrain sustainable public health initiatives. We argue that strategies towards health promotion are not sufficiently integrated with strategies for sustainable development, and thus political strategies aimed at solving health problems or sustainability problems may cause new, undesired and unforeseen environmental or health problems. First, we explore how the relation between health and sustainability is articulated in international policy documents. Next, we develop a model for understanding the relation between health promotion and sustainability. Third, we use examples from agriculture and food production to illustrate that health and sustainability are mutually enabling and constraining. We conclude that while the renewed focus on food security and food inequalities has brought the health and sustainability dimensions of the food system onto the political agenda, the conceptualization of duality between health and sustainability could be a new platform for a critical and theoretical stance towards the market-oriented food system strategy. Thinking along the lines of duality means that the integration of health promotion strategies and sustainable development strategies cannot be based on an approach to integration in which either health or sustainability is given precedence over the other. From a duality perspective, integration means conceiving sustainability from a health perspective and health from a sustainability perspective. PMID:23300191

  9. Research on Sustainable Steelmaking

    NASA Astrophysics Data System (ADS)

    Fruehan, R. J.

    2009-04-01

    The international steel community is faced with the challenge of developing processes that will make steel production more sustainable in the future. Specifically, processes that produce less CO2 and less net waste materials and emissions and that consume less energy are required. This article outlines where energy consumption and CO2 emissions are high and can be reduced. Reductions can be achieved by incremental improvements to existing processes or by a “break-through innovative process”; both strategies are examined. Since most of the energy consumption and CO2 generation occur in ironmaking, research in this area is emphasized. Research on controlling the cohesive zone in the blast furnace, improving the final stages of reduction in direct reduction processes, the use of biomass, and other innovative processes for ironmaking are reviewed. In oxygen steelmaking, improved postcombustion (PC) to allow for more scrap melting is examined. Postcombustion and slag foaming in the electric arc furnace (EAF) in order to reduce energy is reviewed.

  10. What is sustainability and what influences it?

    SciTech Connect

    Schock, R.N.

    1997-06-04

    I was asked to speak on the subject of ``What do we mean by sustainability and what factors have the most impact on it?`` I am afraid I must admit that if there is a generally accepted definition of sustainability, at least as applied to mankind and terrestrial systems, then I am not aware of it. But I expect you know that, or you would not be having this session. The subject of sustainability is one that interests us all. In fact, I think that it fascinates us all because the concept is one to which we can intimately relate. Sustainability implies eternal life; and throughout history, humankind has sought, sometimes secretly, sometimes openly, eternal life, if not for ourselves at least for our progeny. What I will try to do is (1) briefly discuss some of what has been said about this topic, (2) propose a definition that I believe is workable, and point out some of the issues that derive from it, and then (3) suggest what I think we can all do to ensure the sustainability of the planet. I confess to you at the outset that I am an optimist on this subject, and a technological optimist at that. By that I mean that I believe that humans and technology are inextricably linked and that technology provides one of the great keys to helping human beings achieve their goals. I also believe that sustainability is an achievable goal and that it is not a concept to be feared, either intrinsically or economically.

  11. [Health and environmental governance for sustainable development].

    PubMed

    Buss, Paulo Marchiori; Machado, Jorge Mesquita Huet; Gallo, Edmundo; Magalhães, Danielly de Paiva; Setti, Andréia Faraoni Freitas; Franco Netto, Francisco de Abreu; Buss, Daniel Forsin

    2012-06-01

    The United Nations Conference on Sustainable Development, Rio+20, will address the challenges for sustainable development (SD), 'green economy and poverty eradication' and the 'institutional structure of sustainable development'. Therefore it will address the governance needed to achieve such goals. This paper discusses the structure of global, regional and national governance of and for health and environment in the context of SD. Among other global actions, the Millenium Development Goals were a significant recent political effort, but despite its advances, it fails when ignores the structural causes of production and consumption patterns and the unequal distribution of power, which are responsible for inequities and impede true development. To achieve SD, proposals must avoid reductionism, advancing conceptually and methodologically to face the challenges of the socio-environmental determinants of health through intersectoral action, including social participation and all levels of government. It is paramount to continue the implementation of Agenda 21, to meet the MDGs and to create 'Sustainable Development Goals'. Regarding the health field, Rio+20 Summit must reassure the connection between health and sustainability - as a part of the Social pillar of sustainable development - inspiring politics and actions in multiple levels. PMID:22699639

  12. Practical appraisal of sustainable development-Methodologies for sustainability measurement at settlement level

    SciTech Connect

    Moles, Richard; Foley, Walter; Morrissey, John; O'Regan, Bernadette

    2008-02-15

    This paper investigates the relationships between settlement size, functionality, geographic location and sustainable development. Analysis was carried out on a sample of 79 Irish settlements, located in three regional clusters. Two methods were selected to model the level of sustainability achieved in settlements, namely, Metabolism Accounting and Modelling of Material and Energy Flows (MA) and Sustainable Development Index Modelling. MA is a systematic assessment of the flows and stocks of material within a system defined in space and time. The metabolism of most settlements is essentially linear, with resources flowing through the urban system. The objective of this research on material and energy flows was to provide information that might aid in the development of a more circular pattern of urban metabolism, vital to sustainable development. In addition to MA, a set of forty indicators were identified and developed. These target important aspects of sustainable development: transport, environmental quality, equity and quality of life issues. Sustainability indices were derived through aggregation of indicators to measure dimensions of sustainable development. Similar relationships between settlement attributes and sustainability were found following both methods, and these were subsequently integrated to provide a single measure. Analysis identified those attributes of settlements preventing, impeding or promoting progress towards sustainability.

  13. Our Commitment to Bioenergy Sustainability

    SciTech Connect

    2015-06-18

    The U.S. Department of Energy’s Bioenergy Technologies Office (BETO) is committed to developing the resources, technologies, and systems needed to support a thriving bioenergy industry that protects natural resources and ad- vances environmental, economic, and social benefits. BETO’s Sustainability Technology Area proactively identifies and addresses issues that affect the scale-up potential, public acceptance, and long-term viability of advanced bioenergy systems; as a result, the area is critical to achieving BETO’s overall goals.

  14. [What is sustainability science?].

    PubMed

    Wu, Jian-Guo; Guo, Xiao-Chuan; Yang, Jie; Qian, Gui-Xia; Niu, Jian-Ming; Liang, Cun-Zhu; Zhang, Qing; Li, Ang

    2014-01-01

    Sustainability is the theme of our time and also the grandest challenge to humanity. Since the 1970s, the term, sustainable development, has frequently appeared in the scientific literature, governmental documents, media promotions for public goods, and commercial advertisements. However, the science that provides the theoretical foundation and practical guidance for sustainable development--sustainability science--only began to emerge in the beginning of the 21st century. Nevertheless, the field has rapidly developed in depth and expanded in scope during the past decade, with its core concepts and research methods coalescing. China, as the most populous country in the world and home to the philosophical root of sustainability science-the unity of man and nature, is obligated to take upon the challenge of our time, to facilitate global sustainability while pursuing the Chinese Dream, and to play a leading role in the development of sustainability science. Toward this grandiose goal, this paper presents the first Chinese introduction to sustainability science, which discusses its basic concepts, research questions, and future directions. Sustainability science is the study of the dynamic relationship between humans and the environment, particularly focusing on the vulnerability, robustness, resilience, and stability of the coupled human-environment system. It is a transdisciplinary science that integrates natural sciences with humanities and social sciences. It hinges on the environment-economy-society nexus, and merges basic and applied research. The key components of sustainability often change with time, place, and culture, and thus sustainability science needs to emphasize multi-scale studies in space and time, with emphasis on landscapes and regions over a horizon of 50 to 100 years. It needs to focus on the relationship between ecosystem services and human well-being, as influenced by biodiversity and ecosystem processes as well as climate change, land use

  15. Achieving yield gains in wheat.

    PubMed

    Reynolds, Matthew; Foulkes, John; Furbank, Robert; Griffiths, Simon; King, Julie; Murchie, Erik; Parry, Martin; Slafer, Gustavo

    2012-10-01

    Wheat provides 20% of calories and protein consumed by humans. Recent genetic gains are <1% per annum (p.a.), insufficient to meet future demand. The Wheat Yield Consortium brings expertise in photosynthesis, crop adaptation and genetics to a common breeding platform. Theory suggest radiation use efficiency (RUE) of wheat could be increased ~50%; strategies include modifying specificity, catalytic rate and regulation of Rubisco, up-regulating Calvin cycle enzymes, introducing chloroplast CO(2) concentrating mechanisms, optimizing light and N distribution of canopies while minimizing photoinhibition, and increasing spike photosynthesis. Maximum yield expression will also require dynamic optimization of source: sink so that dry matter partitioning to reproductive structures is not at the cost of the roots, stems and leaves needed to maintain physiological and structural integrity. Crop development should favour spike fertility to maximize harvest index so phenology must be tailored to different photoperiods, and sensitivity to unpredictable weather must be modulated to reduce conservative responses that reduce harvest index. Strategic crossing of complementary physiological traits will be augmented with wide crossing, while genome-wide selection and high throughput phenotyping and genotyping will increase efficiency of progeny screening. To ensure investment in breeding achieves agronomic impact, sustainable crop management must also be promoted through crop improvement networks. PMID:22860982

  16. Collaborative procurement for developing a sustainable campus

    NASA Astrophysics Data System (ADS)

    Nifa, Faizatul Akmar Abdul; Rahim, Syukran Abdul; Rani, Wan Nurul Mardiah Wan Mohd; Ismail, Mohd. Noorizhar

    2016-08-01

    It is particularly challenging to achieve sustainability in campus universities, where a high volume of users and activities has made it more imperative to promote green buildings that reduce energy and water consumption while having a minimal carbon footprint. At present, the frameworks for sustainable campus have seldom focused on the project procurement method which would improve construction team integration in developing the physical aspect of campus development. Therefore, in response to that challenge, this paper investigates how the delivery team, responsible for the design and construction of a project, can be integrated to work together more efficiently and more using the collaborative procurement method known as partnering. This paper reports part of a previous research and sets the base for ongoing research on the critical factors in partnering for sustainable campus development. The outcome or result of this study will meet and support the requirement for construction, maintenance, and operation process for universities towards sustainable building/campus in the future.

  17. Explorations in achievement motivation

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.

    1982-01-01

    Recent research on the nature of achievement motivation is reviewed. A three-factor model of intrinsic motives is presented and related to various criteria of performance, job satisfaction and leisure activities. The relationships between intrinsic and extrinsic motives are discussed. Needed areas for future research are described.

  18. Achieving health care affordability.

    PubMed

    Payson, Norman C

    2002-10-01

    Not all plans are jumping headlong into the consumer-centric arena. In this article, the CEO of Oxford Health Plans discusses how advanced managed care can achieve what other consumer-centric programs seek to do--provide affordable, quality health care. PMID:12391815

  19. Issues in Achievement Testing.

    ERIC Educational Resources Information Center

    Baker, Eva L.

    This booklet is intended to help school personnel, parents, students, and members of the community understand concepts and research relating to achievement testing in public schools. The paper's sections include: (1) test use with direct effects on students (test of certification, selection, and placement); (2) test use with indirect effects on…

  20. Achieving Peace through Education.

    ERIC Educational Resources Information Center

    Clarken, Rodney H.

    While it is generally agreed that peace is desirable, there are barriers to achieving a peaceful world. These barriers are classified into three major areas: (1) an erroneous view of human nature; (2) injustice; and (3) fear of world unity. In a discussion of these barriers, it is noted that although the consciousness and conscience of the world…