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951.
Perla Pérez-Treviño Héctor Hernández-De la Cerda Jorge Pérez-Treviño Oscar Raúl Fajardo-Ramírez Noemí García Julio Altamirano 《Translational oncology》2018,11(3):672-685
Patients with breast cancer (BC) overexpressing HER2 (HER2+) are selected for Trastuzumab treatment, which blocks HER2 and improves cancer prognosis. However, HER2+ diagnosis, by the gold standard, immunohistochemistry, could lead to errors, associated to: a) variability in sample manipulation (thin 2D sections), b) use of subjective algorithms, and c) heterogeneity of HER2 expression within the tissue. Therefore, we explored HER2 3D detection by multiplexed imaging of Affibody-Quantum Dots conjugates (Aff-QD), ratiometric analysis (RMAFI) and thresholding, using BC multicellular tumor spheroids (BC-MTS) (~120 μm of diameter) as 3D model of BC. HER2+, HER2– and hybrid HER2+/? BC-MTS (mimicking heterogeneous tissue) were incubated simultaneously with two Aff-QD probes (anti-HER2 and negative control (NC), respectively, (1:1)). Confocal XY sections were recorded along the Z distance, and processed by automatized RMAFI (anti-HER2 Aff-QD/ NC). Quantifying the NC fluorescence allowed to predict the fraction of non-specific accumulation of the anti-HER2 probe within the thick sample, and resolve the specific HER2 level. HER2 was detected up to 30 μm within intact BC-MTS, however, permeabilization improved detection up to 70 μm. Specific HER2 signal was objectively quantified, and HER2 3D-density of 9.2, 48.3 and 30.8% were obtained in HER2?, HER2+ and hybrid HER2+/? permeabilized BC-MTS, respectively. Therefore, by combining the multiplexing capacity of Aff-QD probes and RMAFI, we overcame the challenge of non-specific probe accumulation in 3D samples with minimal processing, yielding a fast, specific spatial HER2 detection and objective quantification. 相似文献
952.
P. A. CROSS 《Cytopathology》1997,8(2):79-84
Rapid rescreening of cervical smears as a quality control method The use of a rapid rescreening method as part of an internal quality control programme is reported. During a 12-month period 33 976 smears were reviewed (90.9% of total workload). Two-hundred and nineteen reports were altered, with 23 dyskaryotic smears identified, a false-negative rate of 0.07%, a false-negative dyskaryotic rate of 1.7%. Smears reported as dyskaryotic were also subjected to the rapid screening method (with 86.8% correctly identified) as well as using the method to assess smears before the usual primary screen (with 67.2% of dyskaryotic smears correctly identified). Rapid rescreening as a quality control method is effective, and although it has limitations, should replace 10% proportional rescreening as the preferred daily quality control method of choice. La relecture rapide des frottis cervico-utérins comme méthode de contrôle de qualité Ce travail décrit l'utilisation de la méthode de relecture rapide dans le cadre d'un programme de contrôle de qualité interne. Pendant une période de 12 mois, 33 976 frottis ont été revus (90,9% du recrutement). Deux cent dix neuf comptes-rendus ont été modifiés dont 23 concernant des frottis avec dyscaryoses, ce qui donne un taux de faux négatifs de 0,07% et un taux de faux négatifs pour les dyscaryoses de 1,7%. La méthode rapide a été appliquée à la relecture des frottis initialement classés comme dyscaryotiques (86,8% ont été correctement identifiés) ainsi qu'a la lecture de frottis avant le screening primaire (avec 67,2% de frottis dyscaryotiques correctement identifiés). La méthode de relecture rapide utilisée comme méthode de contrôle de qualité est efficace et, malgré ses limitations, elle devrait remplacer la relecture de 10% comme méthode de contrôle de qualité de routine. Rasches Nachscreenen als Methode der Qualitätskontrolle Während 12 Monaten wurden 33.976 Abstriche durch rasches Nachscreenen überprüft (90,9% aller Abstriche). 219 Befunde wurden abgeädert darunter 23 neue Dyskariosen, Dies entspricht einer Rate falsch negativer von 0,07% und falsch negativer Dyskariosen von 1,7%. Sämtliche Dyskariosen wurden ebenfalls überprüft mit einer Ausbeute von 86,8%, während die Methode als Vorlauf vor dem normalen Screening 67,2% erfasste. Trotz ihrer Einschränkungen ist die Methode wirkungsvoll und sollte die übliche Überprüfung von 10% der negativen Abstriche ersetzen. 相似文献
953.
During 1993 a campaing of lithic experiments was carried out near the National Paleolithic Museum and archaeological park
at Isernia La Pineta, with the aim of reproducing the morphologies of the tools found at the Paleolithic site in order to
try to understand the techniques used for their manufacture and the possible uses to which they were put. In this article
the results of this work are presented. The flint artifacts were faithfully reproduced using the same types of raw material
used by the prehistoric artisans, and using a variety of different techniques (anvil technique, direct percussion and bipolar
technique), among which the bipolar technique seems to assume a particular importance.
Of considerable interest is the fact that in the light of the experiments the denticulates and carinated becs, which at the
site of Isernia La Pineta represent more than 90% of what are usually considered “tools” according to the conventional typological
schemes, turned out in fact to be the residue of cores, that is flaking waste. Furthermore, flakes of small dimensions, derived
from flint tablets or flakecores by means of the bipolar technique, were used as cutting tools in different possible activities
and revealed their high degree of functionalism in contrast with the carinated “tools”.
The analysis of the traces of wear have shown that the great majority of these are found on the small unretouched flakes rather
than on the “tools” such as the denticulates and becs, thereby demonstrating that the latter represent blanks for obtaining
real tools, that are the cutting edges of unretouched flakes.
The industry from Isernia is thus shown to be very opportunistic, based on an intense exploitation of raw material and practically
lacking those which, according to the conventional schemes usually adopted, can be considered as retouched “tools”. 相似文献
954.
Summary The use of chemoselective ligation methods and orthogonal protection techniques allows access to Template-Assembled Synthetic Protein (TASP) molecules exhibiting a large variety of packing topologies. This is demonstrated for the synthesis of an antiparallel 4-helical bundle TASP by condensing amphiphilic peptide blocks, containing aldehyde functions at the C- or N-terminus, to a selectively addressable topological template via oxime bond formation. The resulting antiparallel 4-helix TASP is obtained in high yield and shows a template-induced helical conformation. 相似文献
955.
《L'Anthropologie》2018,122(4):626-653
In recent years many issues arose regarding the technological and functional analysis of lithic assemblages dominated by “second rate raw materials” like vein quartz, metamorphic or volcanic rocks. Nevertheless, the technological study of this kind of assemblages and their consequent interpretation seems to be still based on the techno-typological criteria elaborated for flint artefacts, thus leading to the common inference that these lithic assemblages are archaic and mainly linked to opportunistic production systems. Pedra Dreta and Can Garriga, located in the north-east of the Iberian Peninsula, present two small lithic assemblages dominated by local raw materials (vein quartz, quartzite, porphyry, syenite, etc.) and by opportunistic reduction sequences but with the presence of Levallois and discoid châine operatoires. The technological analysis is aimed to answer two main issues that emerged during the study and that can contribute to the study of non-flint lithic assemblages: 1. Which criteria should we adopt to distinguish between discoid and recurrent centripetal Levallois products? 2. Is it possible that the Levallois products are the result rather of the opportunistic and expedient reduction sequences that are dominant in these assemblages than of a real use of the Levallois method? A use-wear analysis has also been conducted for the first time on Pedra Dreta and Can Garriga lithic assemblages. The peculiarities of the lithic raw materials employed made necessary the adoption of specific methodologies and the realization of a particular procedure for the analysis of porphyry's tools. 相似文献
956.
An anatomical and taxonomic analysis of the mammalian record in the locality of La Poma in Salta Province, Argentina, is here presented. This record consists in two specimens exhumed in levels of the Quebrada de los Colorados Formation referred to the middle late Eocene. The first specimen is represented by a partial skull preserving mostly the rostrum and some dental pieces and was identified as a member of Leontiniidae, although it does not bear enough information for generic or specific determination. The second specimen is represented by more complete material, preserving much of the dentition. It was identified as a new species of the genus Pampahippus, traditionally included in the paraphyletic family Notohippidae. The leontiniid here studied presents several plesiomorphic features identified in other taxa of northwestern Argentina, and this material represents a new example of a pre-Deseadan basal morphotype within the family. Regarding the new species of Pampahippus, it shows clear signs of rising hypsodonty, representing the first case for a notoungulate lineage in the Paleogene of northwestern Argentina.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:45D87764-5B63-4487-BAAC-74F8D490AE18 相似文献
957.
958.
The quinazolinone-containing 2,3-disubstituted piperidines febrifugine and isofebrifugine have been the subject of significant research efforts since their occurrence in Dichroa febrifuga and their anti-malarial actions were first described in the late 1940s. Subsequently they have also been shown to be present in other plants belonging to the hydrangea family and various analogues of febrifugine have been prepared in attempts to tune biological properties. The most notable analogue is termed halofuginone and a substantial body of work now demonstrates that this compound possesses potent human disease relevant activities. This review focuses on the literature associated with efforts dedicated towards uncovering the structures of febrifugine and isofebrifugine, the development of practical methods for their synthesis and the syntheses of structural analogues. 相似文献
959.
Gara S. Alonso Abreu José M. Brito Armas Rafael Castro Fuentes 《Revista espa?ola de geriatría y gerontología》2018,53(1):45-53
Alzheimer's disease is the most common cause of dementia in the elderly population. Currently, there are no effective treatments to prevent or delay the natural course of the disease. Numerous studies have provided information about the molecular processes underlying biological ageing and, perhaps more importantly, potential interventions to slow ageing and promote healthy longevity in laboratory model systems. The main issue addressed in this review is whether an intervention that has anti-ageing properties can alter the appearance and/or progression of Alzheimer's disease, a disease in which age is the biggest risk factor. Different anti-ageing interventions have been shown to prevent (and in some cases possibly restore) several parameters recognised as central symptoms to the development of Alzheimer's disease. In addition, they are taking the first steps towards translating these laboratory discoveries into clinical applications. 相似文献
960.
Pilar Zueras Jeroen Spijker Amand Blanes 《Revista espa?ola de geriatría y gerontología》2018,53(2):66-72