Artigos de revistas: "A Lewis b"

1

Rogers, Maureen. "Montague B Lewis". Australasian Journal of Dermatology 55, n.º 3 (agosto de 2014): 229. http://dx.doi.org/10.1111/ajd.12241.

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Tannen, Terrell. "Edward B Lewis". Lancet 364, n.º 9435 (agosto de 2004): 658. http://dx.doi.org/10.1016/s0140-6736(04)16878-5.

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Galperin, Charles. "Lewis Wolpert, Denis Duboule et Edwards B. Lewis". Bulletin d’histoire et d’épistémologie des sciences de la vie Volume 23, n.º 2 (2016): 199. http://dx.doi.org/10.3917/bhesv.232.0199.

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Gillanders, I. "Lewis Gillanders". BMJ 326, n.º 7390 (22 de março de 2003): 662b—662. http://dx.doi.org/10.1136/bmj.326.7390.662/b.

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Juhl, B. R. "Immunohistochemical demonstration and localization of Lewis a and Lewis b determinants in human urothelium." Journal of Histochemistry & Cytochemistry 33, n.º 4 (abril de 1985): 309–14. http://dx.doi.org/10.1177/33.4.2579997.

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In order to obtain baseline information about Lewis antigen expression in human urothelium in order that changes during malignant transformation can be evaluated, urothelium from eight individuals of known erythrocyte Lewis types were stained by a Tween-modified indirect immunoperoxidase staining technique using goat antibodies directed toward the Lewis a and Lewis b determinants and mouse monoclonal antibodies directed toward the Lewis a determinant in serial dilutions. To evaluate the value of the method for tissue Lewis typing, eleven ureters from individuals of unknown erythrocyte Lewis types were stained using goat antibodies. The Lewis antigens were located on the cell membranes and in the cytoplasm of urothelial cells. Goat antibodies identified Lea-b-, Lea+b+, and Lea+b- urothelium. Monoclonal antibodies identified urothelium with both low and high Lewis a antigen expression as well as urothelium with no Lewis a antigen expression. Urothelial Lewis antigen expression correlated with erythrocyte Lewis types in Lea-b+ and Lea+b- individuals. In Lea-b- individuals Lewis determinants were either not detected or were expressed similarly to Lea-b+ individuals. Urothelial Lewis typing were doubtful in two out of the eleven ureters examined. The results imply that knowledge about erythrocyte Lewis type or normal tissue Lewis antigen expression is necessary for the immunohistochemical evaluation of changes in Lewis antigen expression in urothelial tumors.

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Mayerson, Melvin. "Arthur B. Lewis (1909–1996)". American Journal of Orthodontics and Dentofacial Orthopedics 110, n.º 3 (setembro de 1996): 329. http://dx.doi.org/10.1016/s0889-5406(96)80021-7.

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Scott, Matthew P., e Peter A. Lawrence. "Edward B. Lewis (1918–2004)". Nature 431, n.º 7005 (setembro de 2004): 143. http://dx.doi.org/10.1038/431143a.

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Bender, Welcome. "Edward B. Lewis 1918–2004". Nature Genetics 36, n.º 9 (setembro de 2004): 919. http://dx.doi.org/10.1038/ng0904-919.

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Shashidhara, L. S. "Edward B Lewis (1918–2004)". Journal of Genetics 83, n.º 2 (agosto de 2004): 219. http://dx.doi.org/10.1007/bf02729900.

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Winchester, Guil. "Edward B. Lewis 1918–2004". Current Biology 14, n.º 18 (setembro de 2004): R740—R742. http://dx.doi.org/10.1016/j.cub.2004.09.007.

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Mishra, Rakesh K. "Edward B Lewis (1918–2004)". Journal of Biosciences 29, n.º 3 (setembro de 2004): 231–33. http://dx.doi.org/10.1007/bf02702605.

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BLASCHKE, T., e K. GIACOMINI. "Lewis B. Sheiner, 1940-2004". Clinical Pharmacology & Therapeutics 76, n.º 6 (dezembro de 2004): 650–51. http://dx.doi.org/10.1016/j.clpt.2004.08.027.

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Crow, James F., e Welcome Bender. "Edward B. Lewis, 1918–2004". Genetics 168, n.º 4 (1 de dezembro de 2004): 1773–83. http://dx.doi.org/10.1093/genetics/168.4.1773.

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Reddy, G. Naaresh, Rakesh Parida, R. Inostroza-Rivera, Arindam Chakraborty, Puru Jena e Santanab Giri. "Unique reactivity of B in B[Ge9Y3]3 (Y = H, CH3, BO, CN): formation of a Lewis base". Physical Chemistry Chemical Physics 21, n.º 42 (2019): 23301–4. http://dx.doi.org/10.1039/c9cp04361f.

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Boron compounds usually exhibit Lewis acidity at the boron center due to the presence of vacant p-orbitals. But using Zintl-ion based groups (Ge₉Y₃, Y = H, CH₃, BO, CN), we can alter Lewis acid nature of B to a Lewis base.

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King, Jovanka R., Jezabel Varadé e Lennart Hammarström. "Fucosyltransferase Gene Polymorphisms and Lewisb-Negative Status Are Frequent in Swedish Newborns, With Implications for Infectious Disease Susceptibility and Personalized Medicine". Journal of the Pediatric Infectious Diseases Society 8, n.º 6 (9 de dezembro de 2018): 507–18. http://dx.doi.org/10.1093/jpids/piy085.

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Abstract Background Single-nucleotide polymorphisms (SNPs) in the fucosyltransferase genes FUT2 and FUT3 have been associated with susceptibility to various infectious and inflammatory disorders. FUT variations influence the expression of human histo-blood group antigens (HBGAs) (H-type 1 and Lewis), which are highly expressed in the gut and play an important role in microbial attachment, metabolism, colonization, and shaping of the microbiome. In particular, FUT polymorphisms confer susceptibility to specific rotavirus and norovirus genotypes, which has important global health implications. Methods We designed a genotyping method using a nested polymerase chain reaction approach to determine the frequency of SNPs in FUT2 and FUT3, thereby inferring the prevalence of Lewisb-positive, Lewisb-negative, secretor, and nonsecretor phenotypes in 520 Swedish newborns. Results There was an increased frequency of homozygotes for the minor allele for 1 SNP in FUT2 and 4 SNPs in FUT3. Overall, 37.3% of newborns were found to have Lewis b negative phenotypes (Le (a+b−) or Le (a−b−). Using our new, sensitive genotyping method, we were able to genetically define the Le (a−b−) individuals based on their secretor status and found that the frequency of Lewis b negative newborns in our cohort was 28%. Conclusions Given the high frequency of fucosyltransferase polymorphisms observed in our newborn cohort and the implications for disease susceptibility, FUT genotyping might play a future role in personalized health care, including recommendations for disease screening, therapy, and vaccination.

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Orntoft, TF, EH Holmes, P. Johnson, S. Hakomori e H. Clausen. "Differential tissue expression of the Lewis blood group antigens: enzymatic, immunohistologic, and immunochemical evidence for Lewis a and b antigen expression in Le(a-b-) individuals". Blood 77, n.º 6 (15 de março de 1991): 1389–96. http://dx.doi.org/10.1182/blood.v77.6.1389.1389.

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Abstract The Lewis blood group system comprises two main carbohydrate antigens, Le(a) and Le(b). Lewis typing has traditionally been based on serologic determinations using erythrocytes and saliva. Several recent studies have demonstrated that erythrocyte Lewis phenotype may change during pregnancy or disease, and inappropriate Lewis antigens have been found in both normal and neoplastic tissue. To evaluate whether these observations are in conflict with the presently proposed genetic and biosynthetic basis of the Lewis blood group system, we performed a combined enzymatic, immunohistologic, and immunochemical study of Lewis antigen expression in normal and neoplastic tissues, as well as erythrocytes, plasma, and saliva of Le(a-b-)-typed individuals. Of six cancer-bearing patients typed Le(a-b-), three were identified as nongenuine owing to the presence of alpha 1----4fucosyltransferase activity (alpha 1----4FT) and Lewis antigens in saliva and three were identified as genuine (lacking alpha 1----4FT and Lewis antigens in saliva). These genuine Le(a-b-) individuals were shown to express significant alpha 1----4FT in tissues, and Lewis antigens were detected in tissues by immunohistology as well as immunochemistry. We conclude that the Lewis phenotype obtained by serologic determination of erythrocytes and saliva does not apply to all tissues. We discuss biosynthetic and genetic consequences of this finding.

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Orntoft, TF, EH Holmes, P. Johnson, S. Hakomori e H. Clausen. "Differential tissue expression of the Lewis blood group antigens: enzymatic, immunohistologic, and immunochemical evidence for Lewis a and b antigen expression in Le(a-b-) individuals". Blood 77, n.º 6 (15 de março de 1991): 1389–96. http://dx.doi.org/10.1182/blood.v77.6.1389.bloodjournal7761389.

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The Lewis blood group system comprises two main carbohydrate antigens, Le(a) and Le(b). Lewis typing has traditionally been based on serologic determinations using erythrocytes and saliva. Several recent studies have demonstrated that erythrocyte Lewis phenotype may change during pregnancy or disease, and inappropriate Lewis antigens have been found in both normal and neoplastic tissue. To evaluate whether these observations are in conflict with the presently proposed genetic and biosynthetic basis of the Lewis blood group system, we performed a combined enzymatic, immunohistologic, and immunochemical study of Lewis antigen expression in normal and neoplastic tissues, as well as erythrocytes, plasma, and saliva of Le(a-b-)-typed individuals. Of six cancer-bearing patients typed Le(a-b-), three were identified as nongenuine owing to the presence of alpha 1----4fucosyltransferase activity (alpha 1----4FT) and Lewis antigens in saliva and three were identified as genuine (lacking alpha 1----4FT and Lewis antigens in saliva). These genuine Le(a-b-) individuals were shown to express significant alpha 1----4FT in tissues, and Lewis antigens were detected in tissues by immunohistology as well as immunochemistry. We conclude that the Lewis phenotype obtained by serologic determination of erythrocytes and saliva does not apply to all tissues. We discuss biosynthetic and genetic consequences of this finding.

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Hong, Yun Ji, Sang Mee Hwang, Taek Soo Kim, Eun Young Song, Kyoung Un Park, Junghan Song e Kyou-Sup Han. "Significance of Lewis Phenotyping Using Saliva and Gastric Tissue: Comparison with the Lewis Phenotype Inferred fromLewisandSecretorGenotypes". BioMed Research International 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/573652.

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Lewis phenotypes using various types of specimen were compared with the Lewis phenotype predicted fromLewisandSecretorgenotypes. This is the first logical step in explaining the association between the Lewis expression andHelicobacter pylori. We performed a study of the followings on 209 patients who underwent routine gastroscopy: erythrocyte and saliva Lewis phenotyping, gastric Lewis phenotyping by the tissue array, and theLewisandSecretorgenes genotyping. The results of phenotyping were as follows [Le(a−b−), Le(a+b−), Le(a−b+), and Le(a+b+), respectively, in order]: erythrocyte (12.4%, 25.8%, 61.2%, and 0.5%); saliva (2.4%, 27.3%, 70.3%, and 0.0%); gastric mucosa (8.1%, 6.7%, 45.5%, and 39.7%). The frequency ofLe,le59/508,le59/1067, andle59alleles was 74.6%, 21.3%, 3.1%, and 1.0%, respectively, among 418 alleles. The saliva Lewis phenotype was completely consistent with the Lewis phenotype inferred fromLewisandSecretorgenotypes, but that of gastric mucosa could not be predicted from genotypes. Lewis phenotyping using erythrocytes is only adequate for transfusion needs. Saliva testing for the Lewis phenotype is a more reliable method for determining the peripheral Lewis phenotype of an individual and the gastric Lewis phenotype must be used for the study on the association betweenHelicobacter pyloriand the Lewis phenotype.

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19

Dolbeare, Kenneth M., e George Q. Flynn. "Lewis B. Hershey, Mr. Selective Service". American Historical Review 91, n.º 1 (fevereiro de 1986): 208. http://dx.doi.org/10.2307/1867408.

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20

O'Sullivan, John, e George Q. Flynn. "Lewis B. Hershey, Mr. Selective Service". Journal of American History 72, n.º 3 (dezembro de 1985): 741. http://dx.doi.org/10.2307/1904396.

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Lobdell, George H., e George Q. Flynn. "Lewis B. Hershey, Mr. Selective Service." Military Affairs 50, n.º 4 (outubro de 1986): 214. http://dx.doi.org/10.2307/1988018.

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WILLIAMS, CHARLES H. "David Byron Lewis, MD". Radiology 190, n.º 3 (março de 1994): 909. http://dx.doi.org/10.1148/radiology.190.3.909-b.

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GARCES, MIGUEL. "Elbert K. Lewis, M.D". Radiology 156, n.º 3 (setembro de 1985): 847. http://dx.doi.org/10.1148/radiology.156.3.847-b.

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BAKER, GERALD L. "Garner L. Lewis, MD". Radiology 169, n.º 3 (dezembro de 1988): 879. http://dx.doi.org/10.1148/radiology.169.3.879-b.

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Yu, L. C., Y. H. Yang, R. E. Broadberry, Y. H. Chen, Y. S. Chan e M. Lin. "Correlation of a missense mutation in the human Secretorα1,2-fucosyltransferase gene with the Lewis(a+b+) phenotype: a potential molecular basis for the weak Secretor allele (Sew)". Biochemical Journal 312, n.º 2 (1 de dezembro de 1995): 329–32. http://dx.doi.org/10.1042/bj3120329.

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A missense mutation (A385 to T), predicting an Ile129 to Phe substitution, in the human Secretor alpha 1,2-fucosyltransferase gene was present in double dose in Lewis(a+b+) individuals, but not in Lewis(a-b+) individuals. Co-segregation of the Lewis(a+b+) phenotype with homozygosity for the mutation was also verified. These results yield a potential molecular basis for the weak Secretor allele (Sew) accounting for the Lewis(a+b+) phenotype.

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Möricke, Jennifer, Birgit Wibbeling, Constantin G. Daniliuc, Gerald Kehr e Gerhard Erker. "Design and reactions of a carbon Lewis base/boron Lewis acid frustrated Lewis pair". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, n.º 2101 (24 de julho de 2017): 20170015. http://dx.doi.org/10.1098/rsta.2017.0015.

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The conjugated dienamine 4 selectively adds Piers' borane [HB(C 6 F 5 ) 2 ] to give the enamine/borane system 5 , which features a boratirane structure by internal enamine carbon Lewis base to boron Lewis acid interaction. Compound 5 behaves as a C/B frustrated Lewis pair and undergoes typical addition reactions to benzaldehyde, several nitriles and to sulfur dioxide. This article is part of the themed issue ‘Frustrated Lewis pair chemistry’.

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Chase, Preston A., Patricio E. Romero, Warren E. Piers, Masood Parvez e Brian O. Patrick. "Fluorinated 9-borafluorenes vs. conventional perfluoroaryl boranes Comparative Lewis acidity". Canadian Journal of Chemistry 83, n.º 12 (1 de dezembro de 2005): 2098–105. http://dx.doi.org/10.1139/v05-240.

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Perfluorinated 9-phenyl-9-borafluorene, 1, is an antiaromatic analog of the well-known tris(pentafluorophenyl)borane. Spectroscopic, structural, and electrochemical studies have been performed on 1 and its Lewis base adducts with MeCN, THF, and PMe3 with a view to assessing its comparative Lewis acid strength relative to B(C6F5)3. For the sterically undemanding Lewis base MeCN, 1 and B(C6F5)3 have comparable LA strengths, while for more sterically prominent THF, 1 is clearly the stronger Lewis acid (LA) based on competition experiments. We conclude that steric factors, rather than antiaromaticity, are the most important determinants in the LA strength differences between 1 and B(C6F5)3.Key words: boranes, Lewis acids, fluorinated compounds, heterocycles.

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Zhao, Haiyan, Joseph H. Reibenspies e François P. Gabbaï. "Lewis acidic behavior of B(C6Cl5)3". Dalton Trans. 42, n.º 3 (2013): 608–10. http://dx.doi.org/10.1039/c2dt31482g.

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Ishihara, Kazuaki. "ChemInform Abstract: Chiral B(III) Lewis Acids". ChemInform 33, n.º 20 (21 de maio de 2010): no. http://dx.doi.org/10.1002/chin.200220270.

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Ishihara, Kazuaki. "ChemInform Abstract: Achiral B(III) Lewis Acids". ChemInform 33, n.º 20 (21 de maio de 2010): no. http://dx.doi.org/10.1002/chin.200220271.

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Dipta, Tashmim Farhana, Hafizur Rahman, Ayesha Khatun e Md Ashadul Islam. "Prevalence of Lewis Blood Group among Bangladeshi Population". Anwer Khan Modern Medical College Journal 7, n.º 2 (18 de fevereiro de 2017): 12–15. http://dx.doi.org/10.3329/akmmcj.v7i2.31638.

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Background: The Lewis system differs from all other blood group systems. It is primarily a system of soluble antigens originate in the tissue of body secretions, such as saliva (glycoprotein) and in plasma (glycolipid) respectively.The ABH secretor status influences red cells of Lewis phenotype and this phenotype may be modified by the ABO phenotype.Methodology: A cross sectional study was done to determine the presence of Lewis antigens in patients and voluntary donor's blood and observe the agglutination pattern during blood cross matching. In this study 350 blood samples were tested by hemagglutination -monoclonal antibodies.Result: Our study showed, Lewis antibody was detected in 50.8 % cases. The presence of anti-Leb was more frequent (69.7%) than anti-Lea in association with ABO blood group. Lewis anti-Leb was most common in O group (75.0%) followed by group-A (69.0%) where as anti-Lea was predominant in B (37.7%) followed by AB (33.3%).Moreover among Lewis phenotypes, Le (a-b+) was present in 35.4% cases, Le (a+ b-) in 15.1% and Le (a+ b+) was rare (0.3%). Phenotype Le (a-b-) represents all negative cases 172 in number (49.2%).Conclusion: Presence of Lewis antibody cause irregular agglutination interfering with interpretation of compatibility testing. So the patients with multiple transfusions or having atypical or irregular antibodies should routinely test for Lewis blood group antibodies to avoid untoward reactions.Anwer Khan Modern Medical College Journal Vol. 7, No. 2: Jul 2016, P 12-15

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Körte, Leif A., Robin Warner, Yury V. Vishnevskiy, Beate Neumann, Hans-Georg Stammler e Norbert W. Mitzel. "Intramolecular pyridine-based frustrated Lewis-pairs". Dalton Transactions 44, n.º 21 (2015): 9992–10002. http://dx.doi.org/10.1039/c5dt01068c.

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Besides a series of pyridine-based Lewis pairs with B(C₆F₅)₂ groups with varying electronic and steric situations and strong intramolecular B–N bonds, 2-[(CH₂)₄B(C₆F₅)₂]-6-tBu-pyridine was found to behave as a frustrated Lewis pair.

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Erker, Gerhard. "Frustrated Lewis pairs: Some recent developments". Pure and Applied Chemistry 84, n.º 11 (31 de agosto de 2012): 2203–17. http://dx.doi.org/10.1351/pac-con-12-04-07.

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The chemistry of some reactive frustrated Lewis pairs (FLPs) is reported. This includes intramolecular P/B and N/B FLPs, some of which were used as catalysts for the hydrogenation of electron-rich olefin substrates. Some advanced intermolecular FLPs are reported, which includes systems derived from very bulky alkenyl boranes obtained from 1,1-carboboration reactions of 1-alkynes with tris(pentafluorophenyl)borane. Some such systems activate dihydrogen and transfer the resulting proton/hydride pair even to some electron-poor alkynes. Eventually, we report on the reaction of our intramolecular ethylene-bridged P/B FLP with nitric oxide (NO). N,B-addition of the P-Lewis base/B-Lewis acid combination is observed to form a new type of a persistent aminoxyl radical. Some of the chemistry of the new FLP-NO radicals is presented and discussed.

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Körte, Leif A., Sebastian Blomeyer, Shari Heidemeyer, Andreas Mix, Beate Neumann e Norbert W. Mitzel. "Intramolecular cooperativity in frustrated Lewis pairs". Chemical Communications 52, n.º 64 (2016): 9949–52. http://dx.doi.org/10.1039/c6cc05228b.

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The doubly Lewis-acid functionalised aniline PhN[(CH₂)₃B(C₆F₅)₂]₂ features two competing boron functions in fast exchange for binding to the central Lewis base. In contrast to the mono acid-functionalised PhMeN[(CH₂)₃B(C₆F₅)₂], it is an active frustrated Lewis pair.

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Kelleher, C. "Health promotion: shades of Lewis Carroll." Journal of Epidemiology & Community Health 49, n.º 1 (1 de fevereiro de 1995): 1–4. http://dx.doi.org/10.1136/jech.49.1.1-b.

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Choi, Hong Dae, Ji Bong Jang, Pil Ja Seo, Byeng Wha Son e Uk Lee. "2,9-Dimethyl-3,8-bis(methylsulfanyl)naphtho[2,1-b:3,4-b′]difuran". Acta Crystallographica Section E Structure Reports Online 62, n.º 5 (11 de abril de 2006): o1785—o1786. http://dx.doi.org/10.1107/s1600536806012098.

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The title compound, C18H16O2S2, was prepared by the Lewis acid-catalysed reaction of 2,3-dihydroxynaphthalene with α-chloro-α-(methylsulfanyl)acetone. The naphtho[2,1-b:3,4-b′]difuran unit is nearly planar, with a mean deviation from the least-squares plane of 0.028 Å. In the crystal structure, aromatic π–π stacking interactions are observed between adjacent molecules.

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Beebee, Helen. "Counterfactual Dependence and Broken Barometers: A Response to Flichman's Argument". Crítica (México D. F. En línea) 29, n.º 86 (8 de janeiro de 1997): 107–19. http://dx.doi.org/10.22201/iifs.18704905e.1997.1065.

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El artículo consiste en una defensa del análisis contrafáctico de la causación de David Lewis en contra de un argumento presentado por primera vez por Eduardo Flichman. El argumento de Flichman involucra una situación en la cual tienen lugar los tres sucesos siguientes: p : una presión atmosférica de 1000mb b : el funcionamiento correcto del barómetro r : una lectura en el barómetro de 1000mb Si el análisis de Lewis ha de tener éxito, la fórmula contrafáctica (1) ~O(r) □→ ~O(p) debe ser falsa. Pero Lewis mismo justifica la afirmación de que (1) es falsa mediante la siguiente observación: ``Si la lectura hubiese sido más alta, ¿habría habido una mayor presión? O ¿habría estado funcionando mal el barómetro? Lo segundo suena mejor: una lectura más alta habría sido una lectura incorrecta." Flichman infiere de esta aserción que Lewis está comprometido con: (2) ~O(r) □→ ~O(b) Se sigue del análisis de Lewis de la causación que r causó b; y esto, desde luego, es falso. Sostengo que Flichman se equivoca al inferir que Lewis está comprometido con (2) a partir del hecho de que haga la afirmación citada más arriba. Flichman supone que hay cierto suceso b que corresponde al hecho de que el barómetro funcione bien. Pero de hecho la única manera de lograr que (2) sea verdadera es suponer que b puede caracterizarse esencialmente como el hecho de que el barómetro tenga una propiedad disposicional (a saber, la disposición de ofrecer la lectura correcta), y Lewis niega de manera explícita que las propiedades disposicionales puedan ser propiedades esenciales de los sucesos. Por otra parte, si suponemos que la propiedad disposicional es simplemente una característica accidental de b, entonces (2) es falsa. Por lo tanto, la afirmación de Lewis citada más arriba no puede interpretarse razonablemente como la afirmación de que cierto suceso b depende contrafácticamente de r; y, por lo tanto, la objeción de Flichman no funciona. [Traducción: Héctor Islas]

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Chang, Jui-Cheng, Che-Hsuan Yang, I.-Wen Sun, Wen-Yueh Ho e Tzi-Yi Wu. "Synthesis and Properties of Magnetic Aryl-Imidazolium Ionic Liquids with Dual Brønsted/Lewis Acidity". Materials 11, n.º 12 (13 de dezembro de 2018): 2539. http://dx.doi.org/10.3390/ma11122539.

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A series of unique tunable aryl-imidazolium magnetic ionic liquids (MILs) with dual acidity that contain both Brønsted and Lewis acidic sites (abbreviated as B-L MILs) were synthesized and characterized using nuclear magnetic resonance and mass spectrometry. Physical properties, such as thermal properties, magnetic susceptibility, and Brønsted and Lewis acidity, were measured. These properties were found to depend on the cation structure. These B-L MILs had good solubility in many organic solvents, good thermal stability, and low melting points, and exhibited magnet-like behavior. For these B-L MILs, the Brønsted acidity was measured using ultraviolet-visible (UV-Vis), and the Lewis acidity was measured using Fourier transform infrared spectroscopy (FTIR). The results showed that B-L MILs with an electron-withdrawing group in the aryl-imidazolium moiety had higher Brønsted acidity, whereas those with an electron-donating group had higher Lewis acidity. This type of ionic liquid, with both Brønsted and Lewis acidic sites, is expected to be a useful solvent and catalyst for organic reactions.

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Ting, I.-Wen, Tze-Wah Kao, Yen-Ling Chiu, Shyh-Chyi Lo, Fu-Chang Hu e Kwan-Dun Wu. "The Relationship of P1 and Lewis Antigens with Peritoneal Dialysis–Related Escherichia Coli Peritonitis". Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 28, n.º 3_suppl (junho de 2008): 172–78. http://dx.doi.org/10.1177/089686080802803s32.

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It has been known that the P1 and Lewis antigens on red blood cells (RBCs) affect the risk of Escherichia coli–related urinary tract infection. In the present study, we investigated the associations between those antigens and peritoneal dialysis (PD)–related peritonitis and E. coli peritonitis. We recruited 155 patients (66 men, 89 women) who were under PD treatment in July 2005, checked the P1 and Lewis antigen status of their RBCs, reviewed their medical charts, and recorded the dates and the causative pathogens of peritonitis episodes. The relationships between peritonitis and the antigens were analyzed. The mean age of these PD patients was 52.5 ± 14.9 years, and the mean PD duration was 39.8 ± 38.2 months. A total of 66 peritonitis episodes occurred (over 93.4 patient– months) in 41 patients, with 8 patients having more than 1 episode. In particular, E. coli peritonitis accounted for 16 of the 66 peritonitis episodes. We fitted two multiple Cox proportional hazards models (with the robust variance method) for predicting the hazard rates of peritonitis-free and E. coli peritonitis-free survival times to our right-censored data with recurrent events. We found that patients on PD treatment for less than 4 years with (A) lower serum albumin, (B) one or more previous peritonitis episodes, or (C) negative Lewis a and positive Lewis b antigens (secretor) would be at higher risk of peritonitis. And, conditioning on blood type, the PD patients with one or more previous peritonitis episodes and (A) positive P1 antigen, (B) negative Lewis a and positive Lewis b antigens (secretor), or (C) positive Lewis a and negative Lewis b antigens (non-secretor) would be at higher risk of E. coli peritonitis.

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40

Gowda, Ravikumar R., e Eugene Y. X. Chen. "Chemoselective Lewis pair polymerization of renewable multivinyl-functionalized γ-butyrolactones". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, n.º 2101 (24 de julho de 2017): 20170003. http://dx.doi.org/10.1098/rsta.2017.0003.

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Multivinyl-functionalized γ-butyrolactones, γ-vinyl-γ-methyl-α-methylene-γ-butyrolactone ( γ VMMBL) and γ-allyl-γ-methyl-α-methylene-γ-butyrolactone ( γ AMMBL), have been synthesized from biorenewable ethyl levulinate and effectively polymerized by Lewis pairs consisting of an organic N -heterocyclic carbene Lewis base and a strong organo-Lewis acid E(C 6 F 5 ) 3 (E = Al, B). This Lewis pair polymerization is quantitatively chemoselective, proceeds exclusively via polyaddition across the conjugated α-methylene double bond without participation of the γ-vinyl or γ-allyl double bond, and produces high-molecular-weight functionalized polymers with unimodal molecular-weight distributions. The Al-based Lewis pair produces a polymer with approximately 5.5 times higher molecular weight than that produced by the B-based Lewis pair. The resulting vinyl-functionalized polymers are soluble in common organic solvents and stable at room temperature, and can be thermally cured into crosslinked materials. This article is part of the themed issue ‘Frustrated Lewis pair chemistry’.

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Bharath, R. Raj, e P. Arumugam. "The prevalence of secretor status and co-expression of lewis antigen in voluntary blood donors". Asian Journal of Medical Sciences 7, n.º 5 (31 de agosto de 2016): 93–96. http://dx.doi.org/10.3126/ajms.v7i5.14848.

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Background: Blood group substances are present in soluble form in a majority of individuals in secretion such as saliva and body fl uids. Secretor status refers to the presence (SeSe and Sese) or absence (sese) of secretor gene which secrete ABH soluble substances. Secretor status can be used to resolve ABO discrepancies of people whose blood group cannot be identified by routine blood grouping and it can also help in identifying patients who may be a high risk group for getting certain diseases. Aims and Objectives:Our aim and objectives of the study is to fi nd out the Prevalence of Secretor Status and Co-expression of Lewis Antigens among the Voluntary Blood Donors.Materials and Methods:This study was conducted in sixty volunteers and the method used to determine the secretor status was hemagglutination inhibition method. Their blood was used to detect the type of Lewis (Le) antigen since the type of Lewis antigen correlated with the secretor status of the individual.Results:Among the sixty subjects tested, forty fi ve of them were found to be secretors and fifteen of them were Non-secretors. The number of Lewis (a+b-) individuals were twelve, Lewis (a-b+) were thirty nine and Lewis (a-b-) were nine.Conclusion:The prevalence of secretors was 75% and non-secretors were 25% respectively. We found 65 % of the volunteers were found to be Le (a-b+) positive, 20% were Le (a+b-) and the remaining 15% were Le (a-b-) which correlated with the ABH antigen secretor status.Asian Journal of Medical Sciences Vol.7(5) 2016 93-96

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Rothenbacher, Dietrich, Maria Weyermann, Gunter Bode, Murrat Kulaksiz, Bernd Stahl e Hermann Brenner. "Role of Lewis A and Lewis B Blood Group Antigens in Helicobacter pylori Infection". Helicobacter 9, n.º 4 (agosto de 2004): 324–29. http://dx.doi.org/10.1111/j.1083-4389.2004.00236.x.

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Li, Qiuxia, Chao Shi, Manli Huang, Xing Wei, Hong Yan, Chuluo Yang e Aihua Yuan. "B- and N-embedded color-tunable phosphorescent iridium complexes and B–N Lewis adducts with intriguing structural and optical changes". Chemical Science 10, n.º 11 (2019): 3257–63. http://dx.doi.org/10.1039/c8sc04252g.

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Hatakeyama, Masanori. "A Sour Relationship between BabA and Lewis b". Cell Host & Microbe 21, n.º 3 (março de 2017): 318–20. http://dx.doi.org/10.1016/j.chom.2017.02.014.

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45

Brittain, James E. "Electrical Engineering Hall of Fame: Lewis B. Stillwell". Proceedings of the IEEE 96, n.º 3 (março de 2008): 532–35. http://dx.doi.org/10.1109/jproc.2007.913559.

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46

Wang, Long, Shunxi Dong, Constantin G. Daniliuc, Lei Liu, Stefan Grimme, Robert Knitsch, Hellmut Eckert, Michael Ryan Hansen, Gerald Kehr e Gerhard Erker. "Formation of macrocyclic ring systems by carbonylation of trifunctional P/B/B frustrated Lewis pairs". Chemical Science 9, n.º 6 (2018): 1544–50. http://dx.doi.org/10.1039/c7sc04394e.

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The trifunctional P/B/B frustrated Lewis pairs11a–cfeaturing bulky aryl groups at phosphorus [Dmesp (a), Tipp (b), Mes* (c)] were synthesized. Compounds11a,breact with carbon monoxide and form the macrocyclic dimers17a,b, while the carbonylation reaction of the Mes*P/B/B FLP11cgives the macrocyclic trimer18c.

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Abdul, Fatima Rammadan. "Biofilm formation by Staphylococcus aureus isolation from atopic dermatitis patients on defined Lewis types saliva". Journal of University of Babylon 26, n.º 5 (12 de março de 2018): 233–40. http://dx.doi.org/10.29196/jub.v26i5.921.

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Bacteria adherence and biofilm formation vary depending on the strain of microorganism as well as the substrate.Here, we evaluated the ability of different isolates of Staphylococcus aureus (S. aureus), isolated. from atopic dermatitis patients skin and stool to form a biofilm on different Lewis types saliva, including Le (a) , (b) ,(c) and Le a+b+ saliva. S. aureus isolates were cultured on tryptose soy broth.The bacteria were used to form a biofilm on 96- well flat bottom Microtitration plate that was coated with the respective, optimally diluted, processed saliva of Lewis blood groups (a),(b),(c) and Le a+b+.The intensity of biofilm formation was assessed by measuring the biofilm-associated optical density reading of bacterial bound dye. The results indicated a superior ability of biofilm formation on Lewis(a) saliva type.The highest binding gave a mean of 1.25 ± 0.39 compared to biofilm formation on non – coated wells that showed a mean of 0.23 ± 0.016(P=0.01, CL= 0.390 – 1.635). On the other hand, however, a variable degree of binding to Le(b) saliva was demonstrated for the isolates. The isolates didn’t demonstrate binding on Lea-b-(Lec) and Le a+b+ -(Led) saliva. We conclude that biofilm formation on Lewis types saliva of the atopic dermatitis bacterial isolates requires Le(a) in a ligand – receptor-based system for biofilm establishment.

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48

Abdul, Fatima Rammadan. "Biofilm formation by Staphylococcus aureus Isolation from atopic Dermatitis Patients on Defined Lewis Types saliva". JOURNAL OF UNIVERSITY OF BABYLON for Pure and Applied Sciences 26, n.º 5 (12 de março de 2018): 233–40. http://dx.doi.org/10.29196/jubpas.v26i5.921.

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Bacteria adherence and biofilm formation vary depending on the strain of microorganism as well as the substrate.Here, we evaluated the ability of different isolates of Staphylococcus aureus (S. aureus), isolated. from atopic dermatitis patients skin and stool to form a biofilm on different Lewis types saliva, including Le (a) , (b) ,(c) and Le a+b+ saliva. S. aureus isolates were cultured on tryptose soy broth.The bacteria were used to form a biofilm on 96- well flat bottom Microtitration plate that was coated with the respective, optimally diluted, processed saliva of Lewis blood groups (a),(b),(c) and Le a+b+.The intensity of biofilm formation was assessed by measuring the biofilm-associated optical density reading of bacterial bound dye. The results indicated a superior ability of biofilm formation on Lewis(a) saliva type.The highest binding gave a mean of 1.25 ± 0.39 compared to biofilm formation on non – coated wells that showed a mean of 0.23 ± 0.016(P=0.01, CL= 0.390 – 1.635). On the other hand, however, a variable degree of binding to Le(b) saliva was demonstrated for the isolates. The isolates didn’t demonstrate binding on Lea-b-(Lec) and Le a+b+ -(Led) saliva. We conclude that biofilm formation on Lewis types saliva of the atopic dermatitis bacterial isolates requires Le(a) in a ligand – receptor-based system for biofilm establishment.

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49

Cui, Peng, Cezar C. Comanescu e Vlad M. Iluc. "Frustrated Lewis pair-like reactions of nucleophilic palladium carbenes with B(C6F5)3". Chemical Communications 51, n.º 28 (2015): 6206–9. http://dx.doi.org/10.1039/c5cc00868a.

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Nucleophilic palladium carbenes react with the strong Lewis acid B(C₆F₅)₃via remote nucleophilic attack at the para-carbon of the supporting ligand or C–F activation of B(C₆F₅)₃; these reactions indicate frustrated Lewis pair-like behaviour given the steric inaccessibility of the nucleophilic carbene center.

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50

Singh, Bishal K., Mila M. Leuthold e Grant S. Hansman. "Human Noroviruses' Fondness for Histo-Blood Group Antigens". Journal of Virology 89, n.º 4 (26 de novembro de 2014): 2024–40. http://dx.doi.org/10.1128/jvi.02968-14.

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ABSTRACTHuman noroviruses are the dominant cause of outbreaks of gastroenteritis around the world. Human noroviruses interact with the polymorphic human histo-blood group antigens (HBGAs), and this interaction is thought to be important for infection. Indeed, synthetic HBGAs or HBGA-expressing enteric bacteria were shown to enhance norovirus infection in B cells. A number of studies have found a possible relationship between HBGA type and norovirus susceptibility. The genogroup II, genotype 4 (GII.4) noroviruses are the dominant cluster, evolve every other year, and are thought to modify their binding interactions with different HBGA types. Here we show high-resolution X-ray crystal structures of the capsid protruding (P) domains from epidemic GII.4 variants from 2004, 2006, and 2012, cocrystallized with a panel of HBGA types (H type 2, Lewis Y, Lewis B, Lewis A, Lewis X, A type, and B type). Many of the HBGA binding interactions were found to be complex, involving capsid loop movements, alternative HBGA conformations, and HBGA rotations. We showed that a loop (residues 391 to 395) was elegantly repositioned to allow for Lewis Y binding. This loop was also slightly shifted to provide direct hydrogen- and water-mediated bonds with Lewis B. We considered that the flexible loop modulated Lewis HBGA binding. The GII.4 noroviruses have dominated outbreaks over the past decade, which may be explained by their exquisite HBGA binding mechanisms, their fondness for Lewis HBGAs, and their temporal amino acid modifications.IMPORTANCEOur data provide a comprehensive picture of GII.4 P domain and HBGA binding interactions. The exceptionally high resolutions of our X-ray crystal structures allowed us to accurately recognize novel GII.4 P domain interactions with numerous HBGA types. We showed that the GII.4 P domain-HBGA interactions involved complex binding mechanisms that were not previously observed in norovirus structural studies. Many of the GII.4 P domain-HBGA interactions we identified were negative in earlier enzyme-linked immunosorbent assay (ELISA)-based studies. Altogether, our data show that the GII.4 norovirus P domains can accommodate numerous HBGA types.

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