Amplification of Growth Regulatory Genes in Intraductal Breast Cancer Is Associated with Higher Nuclear Grade but Not with the Progression to Invasiveness
摘要:
Ductal carcinoma in situ (DCIS), as an identifiable progenitor lesion of invasive breast cancer, represents a morphologically, biologically, and prognostically heterogeneous disease. It is not clear which molecular mechanisms are involved in progression to infiltrative growth. In this study, 83 DCIS classified according to the Van Nuys grading scheme were examined for amplification of growth regulatory genes that have been found to be amplified in invasive breast cancer (c-erbB2, topoisomerase II alpha, c-myc, and cyclinD1 genes). Exact quantification of gene amplification was enabled by a combination of laser microdissection of paraffin-embedded tissue with real-time PCR. In DCIS, gene amplifications of all tested genes were found. The most frequently amplified gene was c-erbB2 found in 21 of 83 (25%) cases. Amplification of the other genes under investigation was observed in 4% to 6% of cases, high-grade DCIS being predominantly affected. High-grade DCIS differed significantly from low- and intermediate-grade DCIS in frequency and level of c-erbB2 amplification. In addition, high-grade DCIS revealed an accumulation of genetic aberrations. Amplification status in pure in situ lesions did not differ from intraductal carcinoma with an infiltrative component, indicating that although associated with a higher nuclear grade gene amplification might not represent an independent prognostic marker of disease progression.
Über die Silylierung von Aminosäuren und die Peptidsynthese mit Aminosäuretrimethylsilylestern
作者:Hans R. Kricheldorf
DOI:10.1002/jlac.19727630103
日期:1972.11.24
Verschiedene Methoden der SilylierungvonAminosäurenund Oligopeptiden werden untersucht und verglichen. Unter geeigneten Reaktionsbedingungen lassen sich Aminosäurenmit Trimethylchlorsilan quantitativ in Aminosäuretrimethylsilylester 2 oder in N-Trimethylsilyl-aminosäuretrimethylsilylester 1 überführen. Diese werden im Eintopfverfahren direkt zur Peptidsynthese weiterverwendet. Die Reaktivität der Ami
Verschiedene Methoden der Silylierung vonAminosäurenand Oligopeptideide werden untersucht und verglichen。在N-三甲基甲硅烷基-氨基三氨基甲硅烷基酯1中,氨基三甲硅烷基酯2中的三甲基氯硅烷定量分析。Diese werden im Eintopfverfahren direkt zur Peptidsthese weiterverwendet。模具ReaktivitätDERAminosäuretrimethylsilylester 2 gegenüberverschiedenartig aktiviertenAminosäurederivatenwird untersucht UND MIT DER冯Ñ三甲基甲硅烷-aminosäuresilylestern 1 verglichen。
A Facile Synthesis of Acylaminotetraoxysphirophosphoranes
作者:Nan-Jing Zhang、Hai-Yan Lu、Xin Chen、Yu-Fen Zhao
DOI:10.1055/s-1998-2050
日期:1998.4
Acylaminotetraoxyspirophosphorane 4, a new type of pentacoordinated phosphorus compound, was synthesized conveniently by the reaction of N,O-bis(trimethylsilyl)amino acid 2 with ethyl dichlorophosphinite, which was followed by the addition of phenanthrenequinone. This procedure provided an efficient methodology for the preparation of acylaminotetraoxysphirophosphorane and the ring formation of 1,3,2-azaoxaphospholane.
α-Aminosulfonopeptides as possible functional analogs of penicillin; evidence for their extreme instability
作者:Seunguk Paik、Emil H. White
DOI:10.1016/0040-4020(96)00055-5
日期:1996.4
bearing an α-aminosulfonic acid moiety in the penultimate position have been synthesized using a Curtiusrearrangement step. The sulfonopeptides were prepared and examined in aprotic solvents, but they proved to be exceedingly labile in protic solvents; for example, α-acylaminosulfonodipeptide 31 proved to be too unstable to isolate in pure form and its methyl ester, 34, decomposed with a half-life of ca
Silica Metal Oxide Vesicles Catalyze Comprehensive Prebiotic Chemistry
作者:Bruno Mattia Bizzarri、Lorenzo Botta、Maritza Iveth Pérez-Valverde、Raffaele Saladino、Ernesto Di Mauro、Juan Manuel García-Ruiz
DOI:10.1002/chem.201706162
日期:2018.6.7
(NH2CHO), a single‐carbon molecule, at 80 °C. We found that these bilayer membranes, made of amorphous silica and metal oxide/hydroxide nanocrystals, catalyze the condensation of formamide, yielding the four nucleobases of RNA, three amino acids and, several carboxylic acids in a single‐pot experiment. Besides manganese, iron and magnesium, two abundant elements in the earliest Earth crust that are key in