10,449 research outputs found
Structural studies of Pleurotus ostreatus Lectin (POL), a fungal protein of medical interest
No full textLe lectine sono proteine ampiamente diffuse in natura che interagiscono in modo non covalente con i carboidrati. Tra le proteine dei funghi, le lectine sono le più ampiamente studiate perché possono mostrare attività antineoplastica su cellule tumorali umane. Partendo dai corpi fruttiferi del fungo edibile Pleurotus ostreatus è stata isolata una lectina composta da 373 aminoacidi che sembra essere in grado di inibire la crescita delle cellule neoplastiche umane. La lectina chiamata POL, Pleurotus ostreatus lectin, viene purificata mediante due passaggi cromatografici: uno che prevede l’utilizzo di una colonna con una matrice di Sefarosio 4B coniugata con mucina gastrica di maiale o con melibiosio seguita da una colonna a scambio ionico di carbossimetilcellulosa o mediante una gel filtrazione con Sephacryl S-100. Due modi alternativi di eluizione dalla colonna di affinità (con lattosio 0.2 M e con EDTA 5 mM) danno approssimativamente la stessa resa (2-5 mg) di proteina a partire da 500 g di funghi. I dati di diffrazione di raggi X dei cristalli sono stati raccolti in diverse linee della European Synchrotron Radiation Facility (ESRF) di Grenoble, in Francia. La struttura è stata inizialmente risolta per sostituzione isomorfa multipla (Multiple Isomorphous Replacement, MIR) e raffinata fino ad una risoluzione finale di 2.0 Å. L'unità asimmetrica contiene un monomero con due domini contenenti un totale di 22 catene β: 10 formano parte del dominio vicino all’ N terminale e 12 quello al C terminale. Le catene β sono radialmente disposte attorno ad un canale centrale. La lectina è caratterizzata da una debole attività β-glucosidasica (Vmax = 87.21 ± 1.5 nmol sec-1 mg-1, kcat = 0.044 s-1 e Km = 240 ± 0.26 mM) e dalla presenza di due atomi di calcio coordinati in due siti presenti in ciascun dominio.
La POL è stata testata su cellule umane di cancro pancreatico (MiaPaCa-2) e sulle cellule HepG2, una linea cellulare immortale costituita da cellule di carcinoma epatico umano, e il suo effetto terapeutico è risultato evidente.
La POL ricombinante, la cui espressione è stata ottimizzata in E.coli, nonostante cristallizzi in una serie di condizioni, produce cristalli che non diffrangono anche se l'attività enzimatica ed emoagglutinante è preservata.
L’associazione della POL a nanoparticelle di acido poli (lattico-co-glicolico) potrebbe essere sfruttata sia per dirigere i nanocomposti di PLGA verso i tumori sia per l’utilizzo terapeutico della stessa POL incapsulata in nanoparticelle.Lectins are proteins widely diffused in nature that interact non-covalently with carbohydrates. Of all the mushroom proteins, lectins are probably the most extensively investigated because it has been observed that they can exhibit antitumour activity on human cancer cells. A 373 amino acid lectin was isolated from the fruiting bodies of the edible oyster mushroom Pleurotus ostreatus was isolated since it appears to be able to inhibit the growth of human neoplastic cells. The lectin, named POL, Pleurotus ostreatus lectin, and it was purified using two chromatographic steps: a hog gastric mucin or melibiose column followed by a carboxymethyl-cellulose column or a Sephacryl S-100 gel filtration column. Two alternative ways of elution from the affinity column (with lactose 0.2M and with EDTA 5 mM) gave approximately the same yield (2-5 mg) of protein starting with 500 g of mushrooms. X-ray diffraction data of crystals were collected at various beamlines of the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The structure was initially solved by Multiple Isomorphous Replacement (MIR) and it was then refined to a final highest resolution of 2.0 Å. The asymmetric unit contains one monomer with two domains and a total of 22 β-strands: 10 forming the domain closest to the N terminus and 12 nearest the C terminus. The two domains pack face to face and the β-sheet strands are radially arranged around a central tunnel packing face-to-face. The lectin is characterized by a weak β-glucosidase activity (Vmax=87.21±1.5 nmol sec-1 mg-1, kcat=0.044 s-1 and Km=240±0.26 μM) and by the presence of two Calcium atoms coordinated to two sites. POL was tested on human pancreatic cancer cells (MiaPaCa-2) and on HepG2 cells, a perpetual cell line consisting of human liver carcinoma cells, and its therapeutic effect was evident. Recombinant POL, whose expression was optimized in E.coli, crystallized in several conditions but the crystals did not diffract although the enzymatic and hemagglutinating activities were preserved.
Encapsulation and/or binding to poly(lactic-co-glycolic acid) nanoparticles of POL might be exploited both to direct PLGA towards tumours and also to prepare POL-filled nanoparticles for therapeutic purposes
Correspondence: Laura Kephart and Arthur Stupka
No full textThis 1936 correspondence, between Laura Kephart (Mrs. Horace Kephart) and Arthur Stupka, concerns a possible Kephart Memorial. Horace Kephart (1862-1931) was a noted naturalist, woodsman, journalist, and author and promoter of the Great Smoky Mountains National Park. Arthur Stupka (1905-1999) was the first park naturalist to work at the Great Smoky Mountains National Park
Mindscapes: Laura Riding's poetry and poetics /
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão.Esta tese propõe uma leitura revisionista da poesia contemporânea através do exame do caso de um dos mais esquecidos escritores norte-americanos do século XX: Laura (Riding) Jackson (1901-1991). O objetivo é demonstrar que Riding não apenas possuía uma poética definida e singular, mas que ela permanece uma das instâncias mais extremas e paradoxais do modernismo anglo-americano, a ponto de Riding abandonar a escrita da poesia em 1938. Recorrendo a conceitos de "formação do cânone" bem como às noções de "discurso" e "função do autor", em Foucault, investigo a construção do cânone da poesia moderna anglo-americana, recuperando o contexto e as circunstâncias da ocultação de Riding. Enquanto cubro os "discursos" poéticos em circulação na primeira metade do século XX-o "imagismo" de Pound, a "dissociação da sensibilidade", "impersonalidade" e "tradição" de Eliot, a "unidade orgância" e "ambigüidade" da Nova Crítica-ofereço um panorama crítico de modernismos alternativos sendo articulados à época. Minha intenção é demonstrar que os poemas de Riding são expressões vigorosas de um escritor para quem "a mente pensando se torna a força ativa do poema", para usar a apta formulação de Charles Bernstein. Entre minhas descobertas sobre as várias e complexas razões que levaram à não-canonização de Riding estão a hegemonia da Nova Crítica, o exílio voluntário de Riding da cena literária (onde são feitas ou desfeitas as reputações), sua recusa em ser antologiada, bem como em ser explicada em termos críticos que não os dela. Todos esses fatores, mais a "dificuldade" de sua poesia, contribuíram para fazer de Riding "a maior poeta esquecida da poesia norte-americana", como escreveu Kenneth Rexroth. Ajudado pelos insights de dois importantes críticos de poesia norte-americana, Charles Bernstein e Marjorie Perloff, defendo que a "poesia da mente" de Riding-onde o que está em jogo é que o que pensamos ser a nossa realidade-representa uma mudança radical no paradigma da poética modernista: de uma poesia centrada na imagem para uma poesia centrada na linguagem. Focalizando a experiência consciente e o tempo duracional do pensamento presente em seus poemas, concluo que as "pensagens" de Riding têm o objetivo preciso de constatar um fato universal: enquanto seres humanos e pensantes, estamos numa condição permanente chamada linguagem
Letter, Julia Gardiner Tyler to Mrs. Laura Holloway, author of First Ladies, dated September 20, 1869
No full textALS of Julia Gardiner Tyler to Mrs. Laura Holloway, author of First Ladies, dated September 20, 1869, about interviewing other first ladies. ALS.Found in:Mss. 65 T97 Additions, Series 1: Mss. Acc. 1993.19 Addition, 186
Heritage tourism: a case study of the Laura Ingalls Wilder Heritage Site at Pepin, Wisconsin
No full textPlan BMany things must be taken into consideration when developing a heritage tourism site. It can be a wonderful opportunity for the community involved to benefit economically and historically. Heritage tourism can keep alive the heritage and traditions of the communities past. When it is discovered that a heritage site exists, the first step is to consult with the community. A site will not succeed without the acceptance and assistance from the community involved. Once the interest is known, the development process can proceed. After determining that there is a heritage tourism site possibility in their area, a commumity must do research to determine the feasibility of the site, what will make it a success, and how to obtain that success. This study will examine a community with a heritage tourism site that has been successful in developing and maintaining it's site. By conducting this study, other communities seeking information for developing their site will have an example and tool to work with. The site chosen for this study is the Laura Ingalls Wilder site in Pepin, Wisconsin. The town is rich with it's heritage associated with Laura Ingalls Wilder. The development and success for this town will be documented through this study. Laura Ingails Wilder is a perfect choice for examining heritage tourism. The author of many American Pioneer books, she has become famous all over the world. In turn all places that she or her family members lived are or are becoming heritage tourism sites. There are older ones that have been in progress for some years, such as the one in Pepin, and there are ones that are being discovered through the popularity of new books written about Laura's family. These communities would benefi greatly from the information this study will produce. Without the bene-fit of this knowledge communities who are unaccustomed to tourism or the way the other Laura Ingalls Wilder sites operate, may make terrible errors in development, tarnishing the site. This may also reflect badly on the other Laura Ingalls Wilder sites. It is important for new Wilder sites to examine all information and know exactly what they are doing when developing the site. If all the Laura Ingalls Wilder sites can benefit from each other's knowledge and experience it will greatly increase the market for all sites. The more detailed and expansive the sites are about their knowledge and sites to see, the more people are going to want to travel to as many sites as possible, learning all they can about the life of Laura Ingalls Wilder and her family. These sites not only attract Laura Ingalls Wilder fans but all people that are interested in the American Pioneer period of the United States history. This study will provide the knowledge for communities who are developing heritage tourism sites, especially those focusing on Laura Ingalls Wilder. This is a very important study for tourism and especially heritage tourism. When a heritage site is discovered communities run into the barrier of not having the experience and knowledge to develop the site properly. This study will analyze tourism in Pepin, Wisconsin to determine it's successfulness due to the fact that it is a Laura Ingalls Wilder heritage tourism site, and Wfit was developed in a way to provide tourists with a view of Laura Ingalls Wilder's past and the past of many Pioneer Americans. By studying this subject it will allow for many people to benefit. Tourist who are seeking the pleasure of the knowledge of the past, and communities who want to preserve their past and profit from tourism
Core Journal Lists: Classic Tool, New Relevance
No full textReviews the historical context of core journal lists, current uses in collection assessment, and existing methodologies for creating lists. Outlines two next generation core list projects developing new methodologies and integrating novel information/data sources to improve precision: a national-level core psychology list and the other a local institutional core list for the interdisciplinary field of urban studies and planning. The paper is based on the authors’ panel presentation at the 2009 ACRL National Conference (Seattle, Washington) titled “Core Journal Lists Re-viewed and Re-imagined.”This is an electronic version of an article published in Robin A. Paynter, Rose M. Jackson & Laura Bowering Mullen (2010): Core Journal Lists: Classic Tool, New Relevance, Behavioral & Social Sciences Librarian, 29:1, 15-31. Behavioral & Social Sciences Librarian is available online at: http://www.tandfonline.com, http://dx.doi.org/10.1080/01639260903571096Peer reviewe
IATUL 32nd Conference 2011, “Libraries for an Open Environment: Strategies, Technologies and Partnerships,” Warsaw University of Technology, Warsaw, Poland, 29 May-2 June 2011
No full textThis report provides details recorded from the author's attendance at the IATUL 2011 conference in Warsaw, Poland, May 29-June 2, 2011.This is a post-print version of an article that published in Library Hi Tech News. The published version is available at http://www.emeraldinsight.com/journals.htm?issn=0741-9058&volume=28&issue=8&articleid=1958452&show=abstrac
IFLA satellite pre-conference: open access to science information: trends, models and strategies for libraries
No full textThe purpose of this paper is to disseminate information about the IFLA pre-conference in Chania, Crete, Greece on the subject of open access in libraries.This is a post-print version of an article published in Library Hi Tech News. The published version of the article is available at http://www.emeraldinsight.com/journals.htm?issn=0741-9058&volume=27&issue=6/7&articleid=1891644&show=abstrac
Publishers and Librarians: New Dialogues in Challenging Times
No full textThis article is a short "viewpoint" piece on the issues of the relationships that exist between publishers and librarians.Originally published in Issues in Science & Technology Librarianship, and available online at: http://www.istl.org/09-winter/viewpoint.htm
<i>No se sabe</i>: entrevista a Laura Sombra del Río
No full textEntrevista a la profesora de Matemática Laura Sombra del Río, integrante del Instituto de Metodología Alternativa para la Enseñanza de la Ciencia (IMApEC). Se especializa en tecnología informática aplicada a la educación, especialmente de las ciencias duras como la matemática.Al hacer clic en el enlace que figura en "Documentos relacionados", pueden accederse a todos los trabajos de Laura Sombra del Río presentes en el repositorio.Facultad de Ingenierí
- …
