Search results for " SCR."
showing 10 items of 1323 documents
Steroidal saponins from Chlorophytum orchidastrum.
2009
Six new spirostane-type saponins (1−6), named orchidastrosides A−F, and chloromaloside D were isolated from an ethanol extract of the roots of Chlorophytum orchidastrum. The saponins have neotigogenin or neogitogenin as the aglycon and oligosaccharidic chains possessing seven to nine sugar units. Their structures were elucidated mainly by 2D NMR spectroscopic analyses (COSY, TOCSY, NOESY, HSQC, and HMBC) and FABMS and HRESIMS. Compounds 1−6 were tested for cytotoxicity against two human colon cancer cell lines, HCT 116 and HT-29.
Stereocontrol in Diphenylprolinol Silyl Ether Catalyzed Michael Additions : Steric Shielding or Curtin-Hammett Scenario?
2017
The enantioselectivity of amine-catalyzed reactions of aldehydes with electrophiles is often explained by simple steric arguments emphasizing the role of the bulky group of the catalyst that prevents the approach of the electrophile from the more hindered side. This standard steric shielding model has recently been challenged by the discovery of stable downstream intermediates, which appear to be involved in the rate-determining step of the catalytic cycle. The alternative model, referred to as Curtin-Hammett scenario of stereocontrol, assumes that the enantioselectivity is related to the stability and reactivity of downstream intermediates. In our present computational study, we examine th…
Il ruolo dell’empatia nell’alfabetizzazione affettiva [Le rôle de l’empathie dans l’alphabétisation affective],
2014
Il ruolo dell’empatia nell’alfabetizzazione affettiva Solo di recente è sorta una riflessione sull’empatia come categoria pedagogica ed educativa. È al fondo una esperienza di condivisione dei vissuti delle persone incontrate; non è dote spontanea, ma è una virtù che esige di essere formata nelle sue dimensioni costitutive - in questo saggio definite veritativa, etica e dialogale. Così intesa, essa rivela la sua essenzialità per pervenire alla conoscenza di sé; e in particolare la sua insostituibilità per apprendere a cogliere e a significare il proprio modo di sentire. Il lavoro di alfabetizzazione emotiva regolata dal codice empatico è opera innanzitutto di un’intelligenza verbale, per de…
Are credit screening contracts designed for men?
2022
AbstractAccess to credit is key to succeed in business. Theoretical models of credit under asymmetric information classify borrowers and grant or deny credit, typically based on incentive-compatible contracts with collateral. However, if women are particularly risk averse, female borrowers may be wrongly classified and denied credit. We conduct in three countries a laboratory experiment to study this systematic gender difference. Results show that incentive-compatible contracts with collateral fail to disclose women’s private information, while disclosing men’s private information. We suggest that banks should incorporate the gender difference in risk attitudes to avoid the glass ceiling in…
Multicellular tumor spheroids: an underestimated tool is catching up again.
2009
The present article highlights the rationale, potential and flexibility of tumor spheroid mono- and cocultures for implementation into state of the art anti-cancer therapy test platforms. Unlike classical monolayer-based models, spheroids strikingly mirror the 3D cellular context and therapeutically relevant pathophysiological gradients of in vivo tumors. Some concepts for standardization and automation of spheroid culturing, monitoring and analysis are discussed, and the challenges to define the most convenient analytical endpoints for therapy testing are outlined. The potential of spheroids to contribute to either the elimination of poor drug candidates at the pre-animal and pre-clinical …
A convolutional neural network for virtual screening of molecular fingerprints
2019
In the last few years, Deep Learning (DL) gained more and more impact on drug design because it allows a huge increase of the prediction accuracy in many stages of such a complex process. In this paper a Virtual Screening (VS) procedure based on Convolutional Neural Networks (CNN) is presented, that is aimed at classifying a set of candidate compounds as regards their biological activity on a particular target protein. The model has been trained on a dataset of active/inactive compounds with respect to the Cyclin-Dependent Kinase 1 (CDK1) a very important protein family, which is heavily involved in regulating the cell cycle. One qualifying point of the proposed approach is the use of molec…
The non-equilibrium charge screening effects in diffusion-driven systems with pattern formation.
2011
The effects of non-equilibrium charge screening in mixtures of oppositely charged interacting molecules on surfaces are analyzed in a closed system. The dynamics of charge screening and the strong deviation from the standard Debye-Huckel theory are demonstrated via a new formalism based on computing radial distribution functions suited for analyzing both short-range and long-range spacial ordering effects. At long distances the inhomogeneous molecular distribution is limited by diffusion, whereas at short distances (of the order of several coordination spheres) by a balance of short-range (Lennard-Jones) and long-range (Coulomb) interactions. The non-equilibrium charge screening effects in …
Paplašināta spektra β-laktamāzes kodējošo gēnu noteikšana Escherichia coli kultūrās, kas izolētas no mājas cūkām
2017
Darba mērķis bija izpētīt Pārtikas drošības, dzīvnieku veselības un vides zinātniskajā institūtā „BIOR” izolētas Escherichia coli kultūras, nosakot TEM, OXA, SHV, CTX-M I, CTX-M II, CTX-M IV, CMY II un DHA tipa β-laktamāzes gēnu klātbūtni baktēriju kultūru paraugos. Bakalaura darbs izstrādāts 2017. gadā zinātniskā institūta “BIOR” Dzīvnieku slimību diagnostikas laboratorijas Mikrobioloģijas nodaļā un Molekulārās bioloģijas nodaļā. Pētāmie paraugi (Escherichia coli kultūras) bija iegūti no mājas cūku (Sus scrofa domestica) aklo zarnu paraugiem 2016. un 2017. gada VPP “AgroBioRes” ietvaros. Kopā tika analizēti 68 Escherichia coli kultūru paraugi no dažādām saimniecībām. β-lactamāzeskodējošo g…
Cerebral expression of neuroglobin and cytoglobin after deep hypothermic circulatory arrest in neonatal piglets
2010
Deep hypothermic circulatory arrest (DHCA) is used in corrective cardiac surgery for complex congenital heart disease. Endogenous protective mechanisms may be responsible for the prevention of brain damage after hypothermic ischemia. Neuroglobin and cytoglobin are expressed in brain cells and appear to modulate hypoxic-ischemic brain injury. However, their neuroprotective potency is still not understood. Thus the aim of this study was to detect the influence exerted by DHCA on their expression.The effects of DHCA were analyzed in a neonatal piglet model with cardiopulmonary bypass, DHCA of 60 and 120 min and subsequent reperfusion of 6h. Complete histological analysis and changes in the mRN…
The effect of detergents on the basement membrane complex of a biologic scaffold material
2013
The basement membrane complex (BMC) is a critical component of the extracellular matrix (ECM) that supports and facilitates the growth of cells. This study investigates four detergents commonly used in the process of tissue decellularization and their effect upon the BMC. The BMC of porcine urinary bladder was subjected to 3% Triton-X 100, 8 mM 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS), 4% sodium deoxycholate or 1% sodium dodecyl sulfate (SDS) for 24 h. The BMC structure for each treatment group was assessed by immunolabeling, scanning electron microscopy (SEM) and second harmonic generation (SHG) imaging of the fiber network. The composition was assessed by quantif…