Production of the Formed Elements

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CHEMISTRY OF THE RARER ELEMENTS BY Ii. SMITH HOPKINS I'KOFKftHOK OK INOIUMNIG CHKMIHTUY or D. C. HEATH AND COMPANY BOSTON NKW YORK CIHCAIMI LON1X)N COPYRIGHT, 1923, BY D. C. HKATH AND COMPANY FEINTED IK U.S.A. PREFACE THE term "rare elements" is conveniently applied to those members of the Periodic Table* whose chemistry in lit fie known. Home of these* elements are so scarce that their study has of necessity been difficult; others are abundant in nature*, but their development has been retarded by lack of sufficient interest; still others have only recently been discovered, and sufficient time has not yet elapsed for them to lose the interest inherent in newness. The "rare elements 1 * then should be understood to include? those elements which are little known either because of scarcity, neglect, or ignorance. The chemistry of norm* of these elements is developing rapidly, since* we are junt beginning to appreciate something; of their interest and usefulness. Rapid advancement, has followed such an awakening,, and the names of Home Htich substances have become household word*. In other cases interest has been less keen and advancement has been slow. The purpose of this work is to call attention both to the ad- vances which have recently been made in our knowledge* of the so-called "rare" elements and also to the need of further re- search in the development of many of the lens familiar elements. This book is the* outgrowth of it lecture course given for many years at the University of Illinois, first by I>r, Clarence W, Balke, and biter by the author. This course* has been enmi- tially a stuely e>f the Periodic Table with special referemw to the dements which are treated very briefly or entirely ignored in most textbooks on Inorganic Chemistry. f*or the present course a working knowledge of the roittfrion element** IM under- stood, and they are mentioned briefly for the pur|K>Hi* of show- ing the relationship between the rare elements ami their more* familiar neighbors. The ehemiistry of many of the nire* element** in still in a decidedly chaotic! ntate. The literature contain* conflicting Btatenient« r misleaeling di#eu.NMio!}H, ami downright errors In such caaea the author hau attempted U) mUn*t those IV PREFACE which seem to bear the greater weight of authority. Where differences of opinion exist for the settling of which more in- formation is needed, an attempt has been made to present an impartial summary. Care has been exercised to eliminate as far as possible inaccurate, misleading, and untrue statements. It is too much, however, to expect that a book of this sort can be made free from errors either direct or implied. The author will be glad to have his attention called to any undetected errors, for which he alone must be held responsible. Sugges- tions will also be gladly received. In a course which has been developed by. a process of this sort many of the original sources of information have been lost. The writer would be glad to acknowledge his indebtedness to every author from whom information has been received, but this is manifestly impossible, since the material has been col- lected from a very wide range of sources and over a period of several years. Much material has been gleaned from such standard works as: Abegg, Handbuch der anorganischen Chemie; Browning, Introduction to the Rarer Production of the Formed Elements Production of the Formed Elements Bởi: OpenStaxCollege The lifespan of the formed elements is very brief Although one type of leukocyte called memory cells can survive for years, most erythrocytes, leukocytes, and platelets normally live only a few hours to a few weeks Thus, the body must form new blood cells and platelets quickly and continuously When you donate a unit of blood during a blood drive (approximately 475 mL, or about pint), your body typically replaces the donated plasma within 24 hours, but it takes about to weeks to replace the blood cells This restricts the frequency with which donors can contribute their blood The process by which this replacement occurs is called hemopoiesis, or hematopoiesis (from the Greek root haima- = “blood”; -poiesis = “production”) Sites of Hemopoiesis Prior to birth, hemopoiesis occurs in a number of tissues, beginning with the yolk sac of the developing embryo, and continuing in the fetal liver, spleen, lymphatic tissue, and eventually the red bone marrow Following birth, most hemopoiesis occurs in the red marrow, a connective tissue within the spaces of spongy (cancellous) bone tissue In children, hemopoiesis can occur in the medullary cavity of long bones; in adults, the process is largely restricted to the cranial and pelvic bones, the vertebrae, the sternum, and the proximal epiphyses of the femur and humerus Throughout adulthood, the liver and spleen maintain their ability to generate the formed elements This process is referred to as extramedullary hemopoiesis (meaning hemopoiesis outside the medullary cavity of adult bones) When a disease such as bone cancer destroys the bone marrow, causing hemopoiesis to fail, extramedullary hemopoiesis may be initiated Differentiation of Formed Elements from Stem Cells All formed elements arise from stem cells of the red bone marrow Recall that stem cells undergo mitosis plus cytokinesis (cellular division) to give rise to new daughter cells: One of these remains a stem cell and the other differentiates into one of any 1/7 Production of the Formed Elements number of diverse cell types Stem cells may be viewed as occupying a hierarchal system, with some loss of the ability to diversify at each step The totipotent stem cell is the zygote, or fertilized egg The totipotent (toti- = “all”) stem cell gives rise to all cells of the human body The next level is the pluripotent stem cell, which gives rise to multiple types of cells of the body and some of the supporting fetal membranes Beneath this level, the mesenchymal cell is a stem cell that develops only into types of connective tissue, including fibrous connective tissue, bone, cartilage, and blood, but not epithelium, muscle, and nervous tissue One step lower on the hierarchy of stem cells is the hemopoietic stem cell, or hemocytoblast All of the formed elements of blood originate from this specific type of cell Hemopoiesis begins when the hemopoietic stem cell is exposed to appropriate chemical stimuli collectively called hemopoietic growth factors, which prompt it to divide and differentiate One daughter cell remains a hemopoietic stem cell, allowing hemopoiesis to continue The other daughter cell becomes either of two types of more specialized stem cells ([link]): • Lymphoid stem cells give rise to a class of leukocytes known as lymphocytes, which include the various T cells, B cells, and natural killer (NK) cells, all of which function in immunity However, hemopoiesis of lymphocytes progresses somewhat differently from the process for the other formed elements In brief, lymphoid stem cells quickly migrate from the bone marrow to lymphatic tissues, including the lymph nodes, spleen, and thymus, where their production and differentiation continues B cells are so named since they mature in the bone marrow, while T cells mature in the thymus • Myeloid stem cells give rise to all the other formed elements, including the erythrocytes; megakaryocytes that produce platelets; and a myeloblast lineage that gives rise to monocytes and three forms of granular leukocytes: neutrophils, eosinophils, and basophils 2/7 Production of the Formed Elements Hematopoietic System of Bone Marrow Hemopoiesis is the proliferation and differentiation of the formed elements of blood Lymphoid and myeloid stem cells not immediately divide and differentiate into mature formed elements As you can see in [link], there are several intermediate stages of precursor cells (literally, forerunner cells), many of which can be recognized by their names, which have the suffix -blast For instance, megakaryoblasts are the precursors of megakaryocytes, and proerythroblasts become reticulocytes, which eject their nucleus and most other organelles before maturing into erythrocytes Hemopoietic Growth Factors Development from stem cells to precursor cells to mature cells is again initiated by hemopoietic growth factors These include the following: • Erythropoietin (EPO) is a ...P oetry is often easy to recognize but not as easy to define. Poems are usually short, and often rhyme, but not always. The beauty (and, for many, the difficulty) of poetry is its brevity. The writer has to convey an idea or emotion in a very short space. Because there are so few words in a poem, every word counts, and poems are often layered with meaning. That’s where a poem gets its power. One fundamental difference between poetry and prose is structure. Poems, of course, are written in verse. They are meant to be heard as well as read. The meaning in a poem comes not just from the words, but also from how the words sound and how they are arranged on the page.  Types of Poems While poems are often categorized by structure (e.g., sonnets or ballads), a more fundamental way to classify poems is by their general purpose. Poems can be emotive, imagistic, narrative, and argumentative. They can also mourn or celebrate. An emotive poem has as its goal to capture a mood or emotion and to make readers feel that mood or emo- tion. On the next page is an untitled poem by the Russian poet Alexander Pushkin. CHAPTER Poetry POETRY SHARES many of the same elements as fiction, but poetry is a unique genre with its own styles and conventions. This chapter explains what makes poems different from stories and how to read and understand poems. 35 327 I have loved you; even now I may confess, Some embers of my love their fire retain but do not let it cause you more distress, I do not want to sadden you again. Hopeless and tonguetied, yet, I loved you dearly With pangs the jealous and the timid know; So tenderly I loved you—so sincerely; I pray God grant another love you so. An imagistic poem aims to capture a moment and help us experience that moment sensually (through our senses). Here is a powerful two-line imagistic poem by Ezra Pound: In a Station of the Metro The apparition of these faces in the crowd; Petals on a wet, black bough. Narrative poems tell stories, while argumentative poems explore an idea (such as love or valor). Here’s a poem by Robert Frost that does both: The Road Not Taken Two roads diverged in a yellow wood, And sorry I could not travel both And be one traveller, long I stood And looked down one as far as I could To where it bent in the undergrowth; Then took the other, as just as fair, And having perhaps the better claim, Because it was grassy and wanted wear; Though as for that the passing there Had worn them really about the same, And both that morning equally lay In leaves no step had trodden black. Oh, I kept the first for another day! Yet knowing how way leads on to way, I doubted if I should ever come back. I shall be telling this with a sigh Somewhere ages and ages hence: Two roads diverged in a wood, and I—I took the one less traveled by, And that has made all the difference. Elegies and odes are two other common types of poems. An elegy is a poem that laments the loss of some- one or something. An ode, on the other hand, celebrates a person, place, thing, or event. Here are a few lines from John Keats’ (1795–1821) famous poem “Ode on a Gre- cian Urn”: Ah, happy, happy boughs! that cannot shed Your leaves, nor ever bid the spring adieu; And, happy melodist, unwearied, For ever piping songs for ever new; More happy love! more happy, happy love! For ever warm and still to BioMed Central Page 1 of 7 (page number not for citation purposes) Journal of Neuroinflammation Open Access Research Astrocyte production of the chemokine macrophage inflammatory protein-2 is inhibited by the spice principle curcumin at the level of gene transcription Michiyo Tomita* 1 , Brita J Holman 2 , Christopher P Santoro 3 and Thomas J Santoro 1,4 Address: 1 Department of Medicine, University of North Dakota School of Medicine & Health Sciences, 501 North Columbia Road, Grand Forks, ND 58201, USA, 2 Boston University, 140 Commonwealth Avenue, Chestnut Hill, MA 02467, USA, 3 Loyola University – Chicago, 6525 North Sheridan Road, Chicago, IL 60626, USA and 4 Research Service, Fargo VA Medical Center, 2101 Elm Street, Fargo, ND 58102, USA Email: Michiyo Tomita* - mtomita@medicine.nodak.edu; Brita J Holman - bjholman@bu.edu; Christopher P Santoro - csantor@luc.edu; Thomas J Santoro - tsantoro@medicine.nodak.edu * Corresponding author MIP-2astrocytescurcumingene transcriptionchemokinesinflammation Abstract Background: In neuropathological processes associated with neutrophilic infiltrates, such as experimental allergic encephalitis and traumatic injury of the brain, the CXC chemokine, macrophage inflammatory protein-2 (MIP-2) is thought to play a pivotal role in the induction and perpetuation of inflammation in the central nervous system (CNS). The origin of MIP-2 in inflammatory disorders of the brain has not been fully defined but astrocytes appear to be a dominant source of this chemokine. Curcumin is a spice principle in, and constitutes approximately 4 percent of, turmeric. Curcumin's immunomodulating and antioxidant activities suggest that it might be a useful adjunct in the treatment of neurodegenerative illnesses characterized by inflammation. Relatively unexplored, but relevant to its potential therapeutic efficacy in neuroinflammatory syndromes is the effect of curcumin on chemokine production. To examine the possibility that curcumin may influence CNS inflammation by mechanisms distinct from its known anti-oxidant activities, we studied the effect of this spice principle on the synthesis of MIP- 2 by astrocytes. Methods: Primary astrocytes were prepared from neonatal brains of CBA/CaJ mice. The cells were stimulated with lipopolysaccharide in the presence or absence of various amount of curcumin or epigallocatechin gallate. MIP-2 mRNA was analyzed using semi-quantitative PCR and MIP-2 protein production in the culture supernatants was quantified by ELISA. Astrocytes were transfected with a MIP-2 promoter construct, pGL3-MIP-2, and stimulated with lipopolysaccharide in the presence or absence of curcumin. Results: The induction of MIP-2 gene expression and the production of MIP-2 protein were inhibited by curcumin. Curcumin also inhibited lipopolysaccharide-induced transcription of the MIP-2 promoter reporter gene construct in primary astrocytes. However MIP-2 gene induction by lipopolysaccharide was not inhibited by another anti-oxidant, epigallocatechin gallate. Conclusion: Our results indicate that curcumin potently inhibits MIP-2 production at the level of gene transcription and offer further support for its potential use in the treatment of inflammatory conditions of the CNS. This Provisional PDF corresponds to the article as it appeared upon acceptance. Fully formatted PDF and full text (HTML) versions will be made available soon. Heterologous expression and optimization using experimental designs allowed highly efficient production of the PHY US417 phytase in Bacillus subtilis 168 AMB Express 2012, 2:10 doi:10.1186/2191-0855-2-10 Ameny Farhat-Khemakhem (ameny2908@yahoo.fr) Mounira Ben Farhat (mounira.benfarhat@yahoo.fr) Ines Boukhris (i.boukhris@yahoo.fr) Wacim Bejar (wacim.bejar@yahoo.com) Kameleddine Bouchaala (boukameleddine@yahoo.fr) Radhouane Kammoun (radhouan.kammoun@cbs.rnrt.tn) Emmanuelle Maguin (emmanuelle.maguin@inra.jouy.fr) Samir Bejar (samir.bejar@cbs.rnrt.tn) Hichem Chouayekh (hichem.chouayekh@cbs.rnrt.tn) ISSN 2191-0855 Article type Original Submission date 30 November 2011 Acceptance date 26 January 2012 Publication date 26 January 2012 Article URL http://www.amb-express.com/content/2/1/10 This peer-reviewed article was published immediately upon acceptance. It can be downloaded, printed and distributed freely for any purposes (see copyright notice below). Articles in AMB Express are listed in PubMed and archived at PubMed Central. For information about publishing your research in AMB Express go to http://www.amb-express.com/authors/instructions/ For information about other SpringerOpen publications go to http://www.springeropen.com AMB Express © 2012 Farhat-Khemakhem et al. ; licensee Springer. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1 Heterologous expression and optimization using experimental designs allowed highly efficient production of the PHY US417 phytase in Bacillus subtilis 168 Ameny Farhat-Khemakhem, Mounira Ben Farhat, Ines Boukhris, Wacim Bejar, Kameleddine Bouchaala, Radhouane Kammoun, Emmanuelle Maguin 1 , Samir Bejar, Hichem Chouayekh* Laboratoire de Microorganismes et de Biomolécules, Centre de Biotechnologie de Sfax, Université de Sfax, Route de Sidi Mansour Km 6, BP “1177” 3018 Sfax, Tunisie. 1 INRA, UMR1319 Micalis, F-78350 Jouy en Josas, France; AgroParisTech, UMR Micalis, F-78350 Jouy en Josas, France. *Corresponding author: hichem.chouayekh@cbs.rnrt.tn (HC) Tel./fax: +216 74870451. AFK: ameny2908@yahoo.fr MBF: mounira.benfarhat@yahoo.fr IB: i.boukhris@yahoo.fr WB: wacim.bejar@yahoo.com KB: boukameleddine@yahoo.fr RK: radhouan.kammoun@cbs.rnrt.tn EM: emmanuelle.maguin@jouy.inra.fr SB: samir.bejar@cbs.rnrt.tn 2 Abstract To attempt cost-effective production of US417 phytase in Bacillus subtilis, we developed an efficient system for its large-scale production in the generally recognized as safe microorganism B. subtilis 168. Hence, the phy US417 corresponding gene was cloned in the pMSP3535 vector, and for the first time for a plasmid carrying the pAMβ1 replication origin, multimeric forms of the resulting plasmid were used to transform naturally competent B. subtilis 168 cells. Subsequently, a sequential optimization strategy based on Plackett-Burman and Box-Behnken experimental designs was applied to enhance phytase production by the recombinant Bacillus. The maximum phytase activity of 47 U ml -1 was reached in the 1 Ministry of Agriculture & Rural Development Collaboration for Agriculture & Rural Development (CARD) 027/05VIE Effects of Stocking Biomass on Growth, Survival and Production of the Two Sizes of Clam Meretrix lyrata Cultured in the Intertidal Areas And Notes on Hatchery Production of Clam Spat. Nhu Van Can (*)(1) , Chu Chi Thiet (1) and Martin S Kumar (2) (1) Aquaculture Research Sub-Institute for North Central (ARSINC) (2) South Australian Research and Development Institute (SARDI), Australia Paper presents in Workshop on “Better Aquaculture Practices” Nha Trang, 7/2009 2 Abstract This paper mainly focused on providing the impact of stocking biomass on the production of clam. It also provides a brief on hatchery production of clam spat, one of the key achievements which contributed towards better aquaculture practice. The triplicate experiment had been conducted in 50m 2 plots randomly placed in the intertidal areas to evaluate the effects of stocking biomass on survival, growth performance and quality of clam Meretrix lyrata Sowerby, 1851. The two stocking sizes (Mean±SD, cm) at shell length of 1.0±0.2 and 1.7±0.1 were scattered at different biomass: 0.05, 0.1, 0.2, 0.3 kg.m -2 and 0.34, 0.68, 1.36, 2.03 kg.m -2 and named as T1, T2, T3, T4 and T5, T6, T7, T8 respectively. Results shown that meat ratio of the clam were similar regardless of different stocking biomass. The fatty acids were rich in highly unsaturated fatty acids especially docosahexaenoic acid but were variable. In contrast, growth and survival of the clam were strongly affected by the stocking biomass in which, the lower stocking biomass resulted in higher specific growth rate (SGR) and survival rate. The biomass gained therefore was reduced accordingly with increasing of stocking biomass although the increase of final production was evident. However, SGR and survival of the treatments T1, T2 and T3 were not significantly different explained for the highest net profit and investment return of the treatment T3. The stocking biomass of 0.2 kg.m2 therefore, was recommended to maximize profit of the clam cultivation. Establishment of commercial hatcheries through the development of hatchery technology is the most important and tangible outcomes the project VIE 027/05. The production of clams in ponds is another key outcome. The artificial production of clam spats will assist in reducing the pressure of declining wild population of clams. That is one of the important contributions of the project towards Better Aquaculture Practices. 3 Effects of stocking biomass on growth, survival and production of the two sizes of clam Meretrix lyrata cultured in the intertidal areas. Introduction The mollusk production has ... and run the risk of infection, significantly increasing the viscosity of 4/7 Production of the Formed Elements the blood and the potential for transmission of blood-borne pathogens if the blood... all of the above C Which of the following statements about erythropoietin is true? It facilitates the proliferation and differentiation of the erythrocyte lineage 6/7 Production of the Formed Elements. .. it is also used medically in the 3/7 Production of the Formed Elements treatment of certain anemia, specifically those triggered by certain types of cancer, and other disorders in which increased