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991.
Nolan M Sikorski J Jando M Lucas S Lapidus A Glavina Del Rio T Chen F Tice H Pitluck S Cheng JF Chertkov O Sims D Meincke L Brettin T Han C Detter JC Bruce D Goodwin L Land M Hauser L Chang YJ Jeffries CD Ivanova N Mavromatis K Mikhailova N Chen A Palaniappan K Chain P Rohde M Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,2(1):29-37
Streptosporangium roseum Crauch 1955 is the type strain of the species which is the type species of the genus Streptosporangium. The 'pinkish coiled Streptomyces-like organism with a spore case' was isolated from vegetable garden soil in 1955. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a member of the family Streptosporangiaceae, and the second largest microbial genome sequence ever deciphered. The 10,369,518 bp long genome with its 9421 protein-coding and 80 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
992.
Del Rio TG Chertkov O Yasawong M Lucas S Deshpande S Cheng JF Detter C Tapia R Han C Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Pukall R Sikorski J Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lapidus A 《Standards in genomic sciences》2010,3(3):294-303
Intrasporangium calvum Kalakoutskii et al. 1967 is the type species of the genus Intrasporangium, which belongs to the actinobacterial family Intrasporangiaceae. The species is a Gram-positive bacterium that forms a branching mycelium, which tends to break into irregular fragments. The mycelium of this strain may bear intercalary vesicles but does not contain spores. The strain described in this study is an airborne organism that was isolated from a school dining room in 1967. One particularly interesting feature of I. calvum is that the type of its menaquinone is different from all other representatives of the family Intrasporangiaceae. This is the first completed genome sequence from a member of the genus Intrasporangium and also the first sequence from the family Intrasporangiaceae. The 4,024,382 bp long genome with its 3,653 protein-coding and 57 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
993.
Silvia Wojczewski Merlin Willcox Vincent Mubangizi Kathryn Hoffmann Wim Peersman Thomas Niederkrotenthaler Silvia Natukunda Samuel Maling Manfred Maier David Mant Ruth Kutalek 《PloS one》2015,10(4)
Background
Uganda is one of the 57 countries with a critical shortage of health workers. The aim of this study was to determine how the human resources and health service crisis was covered in Ugandan newspapers and, in particular, how the newspapers attributed accountability for problems in the health services.Methods
We collected all articles related to health workers and health services for the calendar year 2012 in the two largest national newspapers in Uganda (collection on daily basis) and in one local newspaper (collection on weekly basis). These articles were analysed qualitatively regarding the main themes covered and attribution of accountability.Results
The two more urban national newspapers published 229 articles on human resources and health services in Uganda (on average over two articles per week), whereas the local more rural newspaper published only a single article on this issue in the 12 month period. The majority of articles described problems in the health service without discussing accountability. The question of accountability is raised in only 46% of articles (106 articles). The responsibility of the government was discussed in 50 articles (21%), and negligence, corruption and misbehaviour by individual health workers was reported in 56 articles (25%). In the articles about corruption (n=35), 60% (21 articles) mention corruption by health workers and 40% (14 articles) mention corruption by government officials. Six articles defended the situation of health workers in Uganda.Conclusions
The coverage of accountability in the Ugandan newspapers surveyed is insufficient to generate informed debate on what political actions need to be taken to improve the crisis in health care and services. There exists not only an “inverse care law” but also an “inverse information law”: those sections of society with the greatest health needs and problems in accessing quality health care receive the least information about health services. 相似文献994.
Manfred Lüdicke 《Zoomorphology》1960,48(6):650-670
Zusammenfassung Die Schnäbel verschiedener Arten von Selenidera, Aulacorhynchus, Pteroglossus und Ramphastos werden in ihrer Form und Größe miteinander verglichen.Die für das soziologische Verhalten der Tukane bedeutsamen Pigmentfelder der Tukanschnäbel zeigen entweder keine erkennbaren Beziehungen zu den verschiedenen Hornlagen und ihren Bildungsstätten, oder aber sie sind in ihrer Ausdehnung als Wurzelbänder, Firststreifen und Farbdifferenzierungen der Schnabelspitzen und -schneiden an die Schnabelgrundstrukturen angelehnt.Außerdem können die Pigmentfelder in besonderen Hornlagen liegen. Auch in diesem Falle wird ein Farbmuster infolge des Hornflusses in mehr proximal gelegenen Teilen des Stratum gerininativum angelegt. Durch Härteunterschiede in den Hornlagen und durch die Abnutzung wird dann das in der Keimschicht angelegte Farbmuster zu dem artspezifischen Zeichnungsmuster des Schnabels. Die Hornzähne auf den Schnabelschneiden werden bei Selenidera maculirostris und bei Pteroglossus torquatus durch hellere Hornteile, die sich durch eine besondere Festigkeit auszeichnen, gebildet. Die dunklen Hornteile sind infolge ihrer weicheren Beschaffenheit einer stärkeren Abnutzung unterworfen.Der im Vergleich zu der Entfernung von der Schnabelbasis aufgezeichnete Abstand der Hornzähne der Schnabelschneiden zeigt trotz der unterschiedlichen Abnutzung häufig eine gleichartige Tendenz des Kurvenverlaufs sowohl bei verschiedenen Individuen der gleichen Art als auch bei einem Vergleich der rechten und linken Schnabelseite, wenn auch Rechts-Links-Verschiedenheiten in der Ausbildung der Hornzähne und der Querbänder beobachtet werden können. Es werden Kurven für die Abstände der Hornzähne von anderen Tukanarten zum Vergleich herangezogen.Für den Schnabel von Selenidera maculirostris wird in Übereinstimmung mit v. Kripp ein bedeutender Schnabelschub bei relativ kleiner Auswirkung der am Quadratum wirksamen Kraft festgestellt. Jedoch besitzt die Jugalspange keinen drehrunden Querschnitt. 相似文献
995.
996.
Markus Kubicek Margit Pacher Dietmar Abraham Klaus Podar Manfred Eulitz Manuela Baccarini 《The Journal of biological chemistry》2002,277(10):7913-7919
Mitogenic stimulation of Raf-1 is a complex yet incompletely understood process involving membrane relocalization and phosphorylation of activating residues. We recently reported that Raf-1-associated protein phosphatase 2A contributes to kinase activation, an effect mediated via Ser-259 of Raf-1. Here, we show that mitogens stimulate Ser-259 dephosphorylation and Raf-1/protein phosphatase 2A association concomitantly with membrane accumulation and activation of Raf-1. Blocking Ser-259 dephosphorylation inhibits the two latter events, but it does not prevent activation of a S259A Raf-1 mutant, which is preferentially localized at the membrane independently of mitogenic stimulation. Inhibition of Ser-259 dephosphorylation has no effect on the activation of membrane-tethered Raf-1 (Raf-1CAAX). These data show that Ser-259 dephosphorylation contributes to Raf-1 activation by supporting its membrane accumulation rather than by increasing the specific activity of the kinase and provide a mechanistic basis for the support of kinase activation by Raf-1-associated protein phosphatase 2A. 相似文献
997.
Hoyer C Zander D Fleischer S Schilhabel M Kroener M Platzer M Clos J 《International journal for parasitology》2004,34(7):803-811
We have isolated a gene, LdGF1, from the protozoan parasite Leishmania donovani. Overexpression of this gene confers a strong selective advantage in liquid culture after stationary phase growth arrest. We could show that recombinant L. donovani or Leishmania major, when overexpressing LdGF1, recover faster from a stationary phase growth arrest than control parasite strains. While no advantage of LdGF1 overexpression could be observed in log phase cultures or after a hydroxyurea-induced S-phase growth arrest, recovery from a cell cycle arrest due to serum deprivation was faster in LdGF1-overexpressing strains. This was found to be due to an accelerated release from a G1 cell cycle arrest. By contrast, in a BALB/c mouse infection system, overexpression of LdGF1 in L. major resulted in reduced virulence. We conclude that increased levels of LdGF1 are beneficiary during recovery from G1 cell cycle arrest, but pose a disadvantage inside a mammalian host. These results are discussed in the context of the observed loss of virulence during in vitro passage of Leishmania parasites. 相似文献
998.
Shuisheng Li Wanshun Li Shoujia Jiang Yi Jing Ling Xiao Yangyang Yu Yun Liu Yanhong Li Dengdong Wang Jiang Li Cheng Peng Jiaxing Chen Danqi Lu Bin Wu Xuanmin Guang Junping Ma Xinxin You Yuqing Yang Su Liu Xiaodong Fang Qiang Gao Qiong Shi Haoran Lin Manfred Schartl Zhen Yue Yong Zhang 《Molecular ecology resources》2023,23(4):920-932
999.
Amari K Boutant E Hofmann C Schmitt-Keichinger C Fernandez-Calvino L Didier P Lerich A Mutterer J Thomas CL Heinlein M Mély Y Maule AJ Ritzenthaler C 《PLoS pathogens》2010,6(9):e1001119
Plasmodesmata (PD) are essential but poorly understood structures in plant cell walls that provide symplastic continuity and intercellular communication pathways between adjacent cells and thus play fundamental roles in development and pathogenesis. Viruses encode movement proteins (MPs) that modify these tightly regulated pores to facilitate their spread from cell to cell. The most striking of these modifications is observed for groups of viruses whose MPs form tubules that assemble in PDs and through which virions are transported to neighbouring cells. The nature of the molecular interactions between viral MPs and PD components and their role in viral movement has remained essentially unknown. Here, we show that the family of PD-located proteins (PDLPs) promotes the movement of viruses that use tubule-guided movement by interacting redundantly with tubule-forming MPs within PDs. Genetic disruption of this interaction leads to reduced tubule formation, delayed infection and attenuated symptoms. Our results implicate PDLPs as PD proteins with receptor-like properties involved the assembly of viral MPs into tubules to promote viral movement. 相似文献
1000.
Piiper A Dikic I Lutz MP Leser J Kronenberger B Elez R Cramer H Müller-Esterl W Zeuzem S 《The Journal of biological chemistry》2002,277(46):43623-43630
In PC12 cells, a well studied model for neuronal differentiation, an elevation in the intracellular cAMP level increases cell survival, stimulates neurite outgrowth, and causes activation of extracellular signal-regulated protein kinase 1 and 2 (ERK1/2). Here we show that an increase in the intracellular cAMP concentration induces tyrosine phosphorylation of two receptor tyrosine kinases, i.e. the epidermal growth factor (EGF) receptor and the high affinity receptor for nerve growth factor (NGF), also termed Trk(A). cAMP-induced tyrosine phosphorylation of the EGF receptor is rapid and correlates with ERK1/2 activation. It occurs also in Panc-1, but not in human mesangial cells. cAMP-induced tyrosine phosphorylation of the NGF receptor is slower and correlates with Akt activation. Inhibition of EGF receptor tyrosine phosphorylation, but not of the NGF receptor, reduces cAMP-induced neurite outgrowth. Expression of dominant-negative Akt does not abolish cAMP-induced survival in serum-free media, but increases cAMP-induced ERK1/2 activation and neurite outgrowth. Together, our results demonstrate that cAMP induces dual signaling in PC12 cells: transactivation of the EGF receptor triggering the ERK1/2 pathway and neurite outgrowth; and transactivation of the NGF receptor promoting Akt activation and thereby modulating ERK1/2 activation and neurite outgrowth. 相似文献